SlideShare a Scribd company logo
TELKOMNIKA, Vol.17, No.6, December 2019, pp.2782~2789
ISSN: 1693-6930, accredited First Grade by Kemenristekdikti, Decree No: 21/E/KPT/2018
DOI: 10.12928/TELKOMNIKA.v17i6.12802 ◼ 2782
Received December 20, 2018; Revised May 25, 2019; Accepted July 2, 2019
A wireless precoding technique for millimetre-wave
MIMO system based on SIC-MMSE
Rounakul Islam Boby*1
, Khaizuran Abdullah2
, A. Z. Jusoh3
,
Nagma Parveen4
, A. L. Asnawi5
Electrical and Computer Engineering,
Kulliyyah of Engineering and International Islamic University Malaysia,
Gombak, Selangor, Malaysia, telp: (+603) 6196 4000.
*Corresponding author, e-mail: rounaqul2020@gmail.com1
, khaizuran@iium.edu.my2
,
azamani@iium.edu.my3
Abstract
A communication method is proposed using Minimum Mean Square Error (MMSE) precoding
and Successive Interference Cancellation (SIC) technique for millimetre-wave multiple-input
multiple-output (mm-Wave MIMO) based wireless communication system. The mm-Wave MIMO
technology for wireless communication system is the base potential technology for its high data transfer
rate followed by data instruction and low power consumption compared to Long-Term Evolution (LTE).
The mm-Wave system is already available in indoor hotspot and Wi-Fi backhaul for its high bandwidth
availability and potential lead to rate of numerous Gbps/user. But, in mobile wireless communication
system this technique is lagging because the channel faces relative orthogonal coordination and multiple
node detection problems while rapid movement of nodes (transmitter and receiver) occur. To improve
the conventional mm-wave MIMO nodal detection and coordination performance, the system processes
data using symbolized error vector technique for linearization. Then the MMSE precoding detection
technique improves the link strength by constantly fitting the channel coefficients based on number of
independent service antennas (M), Signal to Noise Ratio (SNR), Channel Matrix (CM) and mean square
errors (MSE). To maintain sequentially encoded user data connectivity and to overcome data loss, SIC
method is used in combination with MMSE. MATLAB was used to validate the proposed
system performance.
Keywords: channel matrix, millimetre-wave, minimum mean square error, quantized system, successive
interference-cancellation
Copyright © 2019 Universitas Ahmad Dahlan. All rights reserved.
1. Introduction
The communications in the millimetre wave band suffers from increased path loss
exponents, higher shadow fading, blockage and penetration losses, etc., where sub-6 GHz
systems leading to a poorer link margin than legacy systems [1-3]. Spatial sparsity of
the channel along with the use of large antenna arrays motivates a subset of physical layer
beamforming schemes based on directional transmissions for signalling. In this context, there
have been a few studies on the design and performance analysis of directional beamforming/
precoding structures for single-user multi-input multi-output (MIMO) systems [4-7]. However, by
restricting attention to small cell coverage and by reaping the increased array gains from
the use of large antenna arrays at both the base-station and user ends, significant rate
improvements can be realized in practice. These works show that directional schemes are not
only good from an implementation standpoint but are also robust to phase changes across
clusters and allow a smooth trade-off between peak beamforming gain and initial user discovery
latency. There has also been progress in generalizing such directional constructions for
multi-user MIMO transmissions [8-11]. Several recent works have addressed hybrid
beamforming for millimetre wave systems. The problem of finding the optimal precoder and
combiner with a hybrid architecture is posed as a sparse reconstruction problem in [12], leading
to algorithms and solutions based on basis pursuit methods. While the solutions achieve good
performance in certain cases, to address the performance gap between the solution proposed
in [12] and the unconstrained beamformer structure, an iterative scheme is proposed in [13, 14]
relying on a hierarchical training codebook for adaptive estimation of millimetre wave channels.
TELKOMNIKA ISSN: 1693-6930 ◼
A wireless precoding technique for millimetre-wave... (Rounakul Islam Boby)
2783
The authors in [13, 14] show that a few iterations of the scheme are enough to achieve
near-optimal performance. In [15], it is established that a hybrid architecture can approach
the performance of a digital architecture if the number of RF chains is twice that of
the data-streams. A heuristic algorithm with good performance is developed when this condition
is not satisfied. Several other works such as [16, 17] have also explored iterative/algorithmic
solutions for hybrid beamforming.
A common theme that underlies most of these works is the assumption of phase-only
control in the RF/analog domain for the hybrid beamforming architecture. This assumption
makes sense at the user end with a smaller number of antennas (relative to the base-station
end), where operating the PAs below their peak rating across RF chains can lead to
a substantially poor uplink performance. On the other hand, amplitude control (denoted as
amplitude tapering in the antenna theory literature) is necessary at the base-station end with
many antennas for side-lobe management and mitigating out-of-band emissions. Further, given
that the base-station is a network resource, simultaneous amplitude and phase control of
the individual antennas across RF chains is feasible at millimetre wave base-stations at
a low-complexity and cost [18]. The millimetre wave experimental prototype demonstrated in
allows simultaneous amplitude and phase control. Table 1 shows the summary of the related
review papers.
Table 1. Summarization of notable review papers.
Methods Years Advantages Disadvantages
Conventional
mmWave
2016-17 1. High frequency 6GHz. 1. High path loss exponents,
2. higher shadow fading,
3. blockage and penetration losses, etc.
Single user MIMO 2013-16 1. Robust to phase changes across
clusters and allow a smooth trade-off
between peak beamforming gains.
Initial user discovery latency.
1. Large antenna arrays motivate a
subset of physical layer beamforming.
Multi-user MIMO 2014-17 1. Generalizing such directional
constructions for multi-user.
1. Switching mode decrease efficiency.
2. Certain data loss.
Pursuit methods-
based Hybrid
architecture.
2014 1. Increased performance by
addressing the performance gap
between the channel switching.
1. Assumed phase control in the
RF/analog domain, only possible in
small number of antennae.
Digital hybrid
architecture.
2016-17 1. Hybrid beamforming.
2. A heuristic algorithm used for
better performance.
1. Number of RF chains is twice that of
the data-streams.
2. Substantially poor uplink performance.
SAPC mmWave 2017 1. Simultaneous amplitude and
phase control of the individual
antennas across RF chains.
2. Low-complexity and cost.
1. Standard capacity of maximum 127
points.
Hybrid precoding
single-user
mmWave
2017 1. Hybrid precoding/combining is
capable.
2. Same performance of the fully
digital.
1. Failure of dedicated computer or
connection problem can fail the system.
2. Required maintenance.
Hybrid precoding for
multi-user mmWave
2015 1. Combination of RF combiner and
RF beamformer to maximize the
channel gain.
2. Derived as a zero-forcing (ZF)
precoder.
1. For a small plant.
2. Extension not possible.
Mean-squared error
(MSE) hybrid
precoder
2011 1. Maximum likelihood (ML) decoder
and a minimum mean square error
(MMSE) decoder.
2. Window coefficients used to
generate the quantized values.
1. The performance depends on
detection engine.
2. Research Method
The proposed system is a combination of successive interference cancellation (SIC)
and Minimum Mean Square Error (MMSE) or can be written as SIC-MMSE. In this process,
initially, the raw data is sampled and prepared for sub-band packaging according to users’ data
symbol. The coder is joined along with MMSE detection system, which will depend upon user or
operator. The MMSE detection process will continue to do channel pilot sensing, testing signal
quality, estimate the Signal to Noise Ratio (SNR), arrange Channel Matrix (CM) formation,
Channel selection & estimation. The MMSE processed data will be filtered for maximum
◼ ISSN: 1693-6930
TELKOMNIKA Vol. 17, No. 6, December 2019: 2782-2789
2784
correlation detection, which is the part of SIC method. This method is used to detect
the sequentially processed data according to the users’ symbols and regenerate the data to
transfer it through the new channel. While MMSE will constantly monitor the signal quality to
realter the channel coefficient, the SIC will help MMSE to improve its performance by fastly
processing sequential data so that MMSE can reselect any parameters at any moment to
reduce interruption and data loss. At the end of transmission process, the RF modulation will
modulate the data then filter with Spectrum Shaping Filter (SSF) and transmit through
the channel. A synchronizer is used in transmission process to synchronize any disrupted
operation. On the receiver side the signal will be demodulated and reshaped with SSF. After
demodulation the same concept of proposed MMSE will be used to decode the data.
The synchronizer on the receiver side and transmitter side will be synchronized together
through MMSE. Finally, the decoded data will be reframed using same SIC method. This
combination (SIC-MMSE) can reduce the channel shortage and performance losses. The total
process of proposed system for transmission unit and process of receiver unit are shown
in Figure 1.
Figure 1. Proposed system approximation for transmission and receiver
2.1. Symbolize Sampling
A multiple user with multiple nodes for base station (BS) was considered based on time
division duplex (TDD) method where upload and download channel data links consider within
coherence interval in a point to point MIMO system. Considering the system have N numbers of
nodes on a base station per cells having M number of total antennas per cells and K number of
single antennae known as user terminal (UT) in each cell. For K antenna user terminal to base
station J can be expressed as:
Hjk = Bjk Gjk
where, Hjk is the fading’s on J station for K number of single antennae. Bjk is the fading
coefficient of large scale and Gjk is the fading coefficient of small scale [7]. Here, Bjk represent
path loss and shadow fading of the channel. The matrix was denoted by upper case and bold
uppercase used for vector identifications. The Gjk is the total nodal fading effect induced in per
cell’s capacity can be represented by [7],
Gjk = CM (0, Im)
where, C and M are the capacity sum rate & number of BS antennas respectively and Im is
the indication function of M. So,
H = G√𝐵
TELKOMNIKA ISSN: 1693-6930 ◼
A wireless precoding technique for millimetre-wave... (Rounakul Islam Boby)
2785
here, H is channel fading, B represents the large-scale diagonal matrix and G represents
the small-scale matrix each column represents a channel from UT to BS. When the number of
BS antennas increase the channel, the approximates orthogonal matrix will be lim
𝑛→∞
𝐻𝐻 𝐻
= B.
Each terminal is assigned with a pilot sensing for k number of single antennas, the sensing pilot
sk with power equal to, sk,t = [sk1; sk2….skt ]T and at each BS station, ‖𝑠 𝑘 𝑠𝑗
𝐻
‖2 = 0, if j ≠ k and
the transmitted power is equal for all pilots. For the conventional detection the receiver vector
matrix y can be denoted by
y ∈ CM×1 [8] or y = Hx + n (1)
where, C is channel matrix and complex additive white gaussian noise (AWGN) vector, H∈CM×K,
x is the symbol vector sent by K user can be denote by x ∈ Ck×1 and number of nodes n. If
the symbol error vector e then,
e = x - ẋ (2)
here, ẋ is the receiving signal. Assuming correlation parameter σ is known perfectly at the base
stations and h[n] be the channel vector between a UT and a BS at time t. Then [9],
h[t] = σ h [t - 1] + ev[t] (3)
here, t is time index and e[t] is white noise with zero mean and temporal correlation parameter
σ2 obtained through the Yule-Walker equation [7]. The channel model above is known as
the stationary ergodic Gauss-Markov block fading channel model [8].
2.2. MMSE Detection Process
For the MIMO model equation according to reference no [7], where receiving signal
vector ŷ from receiver signal y and the fibrinous norm ‖𝑦‖2 to limit sphere of validity of general
norm.
ŷ = y − H ẋ = H (e + x) (3)
where, x is transmitted symbol massages and ẋ is the received symbol massages. Error vector
e should be zero for ideal communication system. So, that the error detection should be
overcome from receiver signal vector. Some researcher expresses the compressing sensing
methods, where they proposed to naturally consider the symbol error vector e [7].
In compressing sensing methods M should be less then K, but if M becomes more then equal to
K, this system will be impractical. For MIMO multi-antenna mode, the M is generally greater
then equal K, the receiver signal vector later filter by matrix WMMSE is given by:
WMMSE = =
𝐻ℎ
𝐻 𝐻ℎ +𝐼 𝑚
(4)
where, W is a predefine filter matrix, WMMSE is the filter matrix for MMSE matrix for and AWGN
(Gaussian noise) vector n ∈ CM for CM (0, Im) [8]. By Maximum A Posterior (MAP) detection
known as detection system detection method the optimal detection é can be found from
the reference paper no [10].
é ≅ arg max
𝑒∈ ˆA 𝐾
(1 √2𝜋𝜎2⁄ ) exp [
−0.707
𝜎2 ((||ŷ − He||)2
2
] Pr(e) (5)
According to the paper the approximation is because of e and n dependency and may
omit while SNR increases and can be precise at high SNRs [10]. Pr(e) is probability of priority
error symbol. When BPKS values are +1 & -1, ˆA is the finite alphabet having the values -2, 0 &
+2 and for the nonzero value of A´ detection error becomes -2 & 2. If transmitted symbols are
from -1 to 1, then the possibility of the e will be no zeroes from +2 to -2 and possible probability
◼ ISSN: 1693-6930
TELKOMNIKA Vol. 17, No. 6, December 2019: 2782-2789
2786
can be 0.5P. When λ is the degree of sparsity, ||e||= 0.25||e||2
. If, e is the element of ˆA 𝐾
and e
is the symbol error vector for initial iteration, by solving (5):
e=
HHˆy
HHH+0.5 λ
e= 𝑀ˆy; [if, ˆA 𝐾
is finite and initially é= e] (6)
here, M is MMSE detection method with tuneable degree of sparesλ, where, λ is
the replacement of noise. If, Qθ(*) is vector dividing function and θ optimal threshold then,
optimal detection, é=Qθ(e) for discrete function [10]. So, we can rewrite:
é = Qθ(e) = 2sin(e)I ; [||e||>θ] (7)
where, “I” is the indication function. If, the optimal threshold, θ = {θ1, θ2, θ3, …, θn} and for
the non-zero components, e = {0, ±2}; [i.e. ||e||<θ]. Similarly, QPSK detection the equivalent
transform with real (R) and imaginary (I), where I(e) and R(e) parts of x,
é = 2sin [ {R(e) + I(e)} T]; [Where, e ˆA ] (8)
here, y initial receiver signals, n is the Gaussian noise, e(l) is the lth symbol error vector. (8) is
the prior probability detection of e. If, e(l) is non-zero, for the nth entry, 𝑥 𝑛
𝑙−1
is of 𝑥 𝑙−1
, the 𝑦 for
nth entry of lth symbol,
𝑦 𝑛
𝑙
= W(l−1) 𝑒 𝑛
𝑙
+∑ 𝑤 𝑛𝑗
1−𝑙
𝑖≠𝑗 𝑒𝑗
𝑙
+ 𝑥 𝑛
𝑙−1
(9)
so, Gaussian approximates with following variance𝜎,
(𝜎 𝑛
𝑙−1
)2 = ∑ 4(𝜔𝑗𝑛
1−𝑙
)2
𝑝𝑙−1
+ {∑ (𝑙 − 1)𝑛
𝑛
𝑛≠𝑗 } (10)
2.3. SIC Algorithm
Considering the mm-wave MIMO system with Distributed Antenna System (DAS)
configuration, where, number of base antenna MB having k number of single antenna and N
number remote radio heads. If the Q user also equipped with MU antenna, the receiving
antennas, MR = MB + Nk ≥ QMU [19-26]. For Q user MU number flat fading channels, the MMSE
pilot sk was considered before now can be rewritten as vectoral form, sk ∈ CM
u
×1. From
the model as Gauss-Markov block fading channel shown above in (3), the data vector sk have
zero mean.
The SIC algorithm relies on sequential detection receiver signals, where it is required to
equalize the channel matrices WMMSE given in (4), then carrier channels can get the higher
Signal to Interference Noise Ratio (SINR). From the reference no [26] the SINR per symbol for
Ith iteration for the jth number of symbols is thus can be expressed as,
𝑆𝐼𝑁𝑅 𝑗
𝑖
= (𝜎 𝑖
)−2
(𝑎𝑖
)2
(|ski|)2 (13)
where, 𝑎𝑖
is the amplitude, Gaussian approximates variance𝜎, pilot sk for Ith iteration. The fading
matrix Hk for k user, having N+1 submatrix in each remote radio head, then, Hk = [Hk1, Hk2, …,
Hk(N+1)]T. When the symbol is decides according a decision will be made depends on MMSE
operator given in (11). Instead of executing don’t care sign decision, it is possible to use
operator Q as soft switch through the hyperbolic tangent non-linear detector whose argument is
weighted by an estimation of the SINR [26]. So, the expression for sk for Ith iteration can be
given in QPSK constellation as,
𝑠 𝑘𝑖 = 0.707 [tanh{𝑅(𝑦 𝑘𝑖)/(𝜎𝑘𝑖
2
)} + 𝑗 tanh{𝐼(𝑦 𝑘𝑖)/(𝜎𝑘𝑖
2
)}] (14)
finally, for the decoded case in receiver end, while all symbols are retrieved, the don’t care
decision will perform for the resulting output y = (y1, y2, …, yn)T.
TELKOMNIKA ISSN: 1693-6930 ◼
A wireless precoding technique for millimetre-wave... (Rounakul Islam Boby)
2787
3. Measurement and Simulations
For MATLAB simulation we used Gaussian noise as reference with different SNR levels
to analyse the performance of the proposed SIC-MMSE system. In this simulation process we
have compared results with conventional mm-wave MIMO system and MMSE system. For
the simulation process we first considered the number of antennae per cells M=1000. For
the process, initially we detected symbol vector j using conventional MIMO system and
proposed MMSE. For the output SNRs priority probability for conventional and MMSE we
followed equations from the reference papers [7-10] shown in (15):
lim
𝑆𝑁𝑅→∞
log 𝑃𝑐 (𝑆𝑁𝑅)
log 𝑆𝑁𝑅
= −𝑑; lim
𝑆𝑁𝑅→∞
log 𝑃 𝑆𝐼𝐶−𝑀𝑀𝑆𝐸 (𝑆𝑁𝑅)
log 𝑆𝑁𝑅
= −𝑑 (15)
Then, the degree of sparsity λ, can be obtained from λ=ln[
2(1−𝑝)
𝑝
]; Considering
the MMSE linear detection, for the Ith iteration the error probability é for SIC-MMSE based MIMO
was obtained from (8), where optimal threshold 𝜃 𝑛
𝑙
was obtained by solving the (7). This
proposed research was conduct on Time Division Duplex (TDD) method. So, to determine
the Spectral Efficiency (SE) for SIC-MMSE is expressed [27]:
ηhMMSE =
(𝑇 𝑓− 𝑇 𝑝 − 𝑇𝑡)𝑁 𝑖
𝑇 𝑖 𝑁 𝑠
(16)
where Tp = preamble period, Tt = trailer time period, Tf = frame duration and Ns = number of
symbols in a t time slot, Ni = number of information bits. By resoliving the equations in MATLAB
finally we got SE for the SIC-MMSE.
Simulating the proposed system in MATLAB the performance of SIC-MMSE was
achieved. For the comparison and benchmarking we also simulated the conventional
mm-Wave, where the simulation was done by Spectral Efficiency (SE) [bit/s/Hz/cell] vs Number
of BS Antennas (M). Figure 2 shows the comparison of the Spectral Efficiency (SE) with
the increase number of BS antenna at base station for conventional or single millimetre-Wave
system, where it is depicted that spectral efficiency increases from 0 to maximum
136 bits/s/Hz/cell with the increase of base antennas from 0 to 1000. Where, the parameters are
optimized for the better performance, the maximum SE was recorded to 157 bits/s/Hz/cell for
the 1000 number of antennas.
Figure 2. Conventional mm-waves MIMO and optimized mm-waves MIMO spectral efficiency
performance with the increase number of Antennas.
The SIC-MMSE simulation in Figure 3 shows better performance than conventional
mm-Wave MIMO system after optimization. Before optimization the maximum SE was found to
133~132 bits/s/Hz/cell while number of antennas was maximum. Where, after optimization
◼ ISSN: 1693-6930
TELKOMNIKA Vol. 17, No. 6, December 2019: 2782-2789
2788
the value crossed 195 bits/s/Hz/cell. Every system requires optimization, where this proposed
system performed almost the equal to optimized conventional mm-wave MIMO system, but after
optimization it rapidly increased. Figure 4 shows the performance comparison simulation block
for the both methods having same parameters, spectral efficiency according to increase number
of antennas.
Figure 3. Proposed SIC-MMSE and optimized
SIC-MMSE spectral efficiency performance
according to increase number of antennas
Figure 4. The performance of both methods’
spectral efficiency according to increase
number of antennas
4. Conclusion and Future Work
This paper has presented a communication method which is the combined methodology
of MMSE and SIC technique for mm-Wave MIMO based wireless communication system.
The combined method was proposed to reduce the relative orthogonal coordination and multiple
node detection problem while transmitter or receiver moves. The development of the equations
was done by comparing, reading and reoptimizing the existed several concepts. From
the simulation it can found that, the proposed combined technique for wireless power
communication is better than conventional mm-wave MIMO. Though, the Proposed SIC-MMSE
require optimization for better performance more combined technique with better optimization
can lead a better performance then single one. In future we would like to improve this research
by adding more system together for optimal performance and compare with recent research.
5. Acknowledgements
This paper was part of works conducted under the IIUM Research Initiative Grant
Scheme (RIGS16-334-0498 & RIGS17-031-0606). The authors would also like to acknowledge
all supports given by the IIUM Research Management Centre through the grant and RAY R&D
for their research support.
References
[1] Aalto University, AT&T, BUPT, CC, Ericsson, Huawei, Intel, KT Corporation, Nokia, NTT DOCOMO,
NYU, Qualcomm, Samsung, U. Bristol, and USC. White paper on 5G channel model for bands up to
100 GHz. 2016 Oct. v2.3.
[2] Sun S, Rappaport TS, Thomas TA, Ghosh A, Nguyen HC, Kovács IZ, Rodriguez I, Koymen O,
Partyka A. Investigation of prediction accuracy, sensitivity, and parameter stability of large-scale
propagation path loss models for 5G wireless communications. IEEE Transactions on Vehicular
Technology. 2016; 65(5): 2843-60.
[3] Raghavan V, Partyka A, Akhoondzadeh-Asl L, Tassoudji MA, Koymen OH, Sanelli J. Millimeter wave
channel measurements and implications for PHY layer design. IEEE Transactions on Antennas and
Propagation. 2017; 65(12): 6521-6533.
[4] Rusek F, Persson D, Lau BK, Larsson EG, Marzetta TL, Edfors O, Tufvesson F. Scaling up MIMO:
Opportunities and challenges with very large arrays. arXiv preprint arXiv: 1201.3210. 2012.
TELKOMNIKA ISSN: 1693-6930 ◼
A wireless precoding technique for millimetre-wave... (Rounakul Islam Boby)
2789
[5] Roh W, Seol JY, Park J, Lee B, Lee J, Kim Y, Cho J, Cheun K, Aryanfar F. Millimeter-wave
beamforming as an enabling technology for 5G cellular communications: Theoretical feasibility and
prototype results. IEEE communications magazine. 2014; 52(2): 106-113.
[6] Raghavan V, Subramanian S, Cezanne J, Sampath A, Koymen OH, Li J. Single-user versus
multi-user precoding for millimeter wave MIMO systems. IEEE Journal on Selected Areas in
Communications. 2017; 35(6): 1387-1401.
[7] Anderson CR, Rappaort TS. In-Building Wideband Partition Loss Measurements at 2.5 GHz and 60
GHz. arXiv preprint arXiv: 1701.03415. 2016.
[8] Raghavan V, Cezanne J, Subramanian S, Sampath A, Koymen O. Beamforming tradeoffs for initial
UE discovery in millimeter-wave MIMO systems. IEEE Journal of Selected Topics in Signal
Processing. 2016; 10(3): 543-559.
[9] Sun S, Rappaport TS, Heath RW, Nix A, Rangan S. MIMO for millimeter-wave wireless
communications: Beamforming, spatial multiplexing, or both?. IEEE Communications Magazine.
2014; 52(12): 110-121.
[10] Raghavan V, Subramanian S, Cezanne J, Sampath A, Koymen O, Li J. Directional hybrid precoding
in millimeter-wave MIMO systems. 2016 IEEE Global Communications Conference (GLOBECOM).
2016: 1-7.
[11] Ran R, Wang J, Oh SK, Hong SN. Sparse-aware minimum mean square error detector for MIMO
systems. IEEE Communications Letters. 2017; 21(10): 2214-2217.
[12] Khaizuran A, Rounakul IB. SIC-MMSE Method based Wireless Precoding Technique for
Millimetre-Wave MIMO System. Indian Journal of Science and Technology. 2019: 12(9): 1-11.
[13] Wang Z, Li M, Liu Q, Swindlehurst AL. Hybrid precoder and combiner design with low-resolution
phase shifters in mmWave MIMO systems. IEEE Journal of Selected Topics in Signal Processing.
2018; 12(2): 256-269.
[14] El Ayach O, Rajagopal S, Abu-Surra S, Pi Z, Heath RW. Spatially sparse precoding in millimeter
wave MIMO systems. IEEE transactions on wireless communications. 2014 Mar; 13(3): 1499-1513.
[15] Venugopal K, Alkhateeb A, Prelcic NG, Heath RW. Channel estimation for hybrid architecture-based
wideband millimeter wave systems. IEEE Journal on Selected Areas in Communications. 2017;
35(9): 1996-2009.
[16] Alkhateeb A, Leus G, Heath RW. Limited feedback hybrid precoding for multi-user millimeter wave
systems. IEEE transactions on wireless communications. 2015; 14(11): 6481-6494.
[17] Sohrabi F, Liu YF, Yu W. One-bit precoding and constellation range design for massive MIMO with
QAM signaling. IEEE Journal of Selected Topics in Signal Processing. 2018; 12(3): 557-570.
[18] Sadeghi M, Björnson E, Larsson EG, Yuen C, Marzetta TL. Max–min fair transmit precoding for
multi-group multicasting in massive MIMO. IEEE Transactions on Wireless Communications. 2018;
17(2): 1358-1373.
[19] Noh S, Zoltowski MD, Love DJ. Training sequence design for feedback assisted hybrid beamforming
in massive MIMO systems. IEEE Transactions on Communications. 2016; 64(1): 187-200.
[20] Russell DS, Fischer LG, Wala PM. Cellular communications system with centralized base stations
and distributed antenna units. US 5,657,374 (Patent). 1997.
[21] Ortega AJ, Sampaio-Neto R. Random-Multi-Branch Successive Interference Cancellation detection in
single-user and multi-user MIMO environments.
[22] Roh W, Paulraj A. MIMO channel capacity for the distributed antenna. Proceedings IEEE 56th
Vehicular Technology Conference. 2002; 2: 706-709.
[23] Zhuang H, Dai L, Xiao L, Yao Y. Spectral efficiency of distributed antenna system with random
antenna layout. Electronics Letters. 2003 20; 39(6): 495-496.
[24] Castanheira D, Gameiro A. Distributed antenna system capacity scaling [coordinated and distributed
mimo]. IEEE Wireless Communications. 2010; 17(3): 68-75.
[25] Shida M. Distributed antenna system. United States patent US 8,923,908. 2014.
[26] Debbah M, Muquet B, De Courville M, Muck M, Simoens S, Loubaton P. A MMSE successive
interference cancellation scheme for a new adjustable hybrid spread OFDM system. VTC2000-Spring
2000 IEEE 51st
Vehicular Technology Conference Proceedings (Cat. No. 00CH37026). 2000; 2:
745-749.

More Related Content

PDF
ICICCE0301
PDF
PERFORMANCE OF MIMO MC-CDMA SYSTEM WITH CHANNEL ESTIMATION AND MMSE EQUALIZATION
PDF
Network efficiency enhancement by reactive channel state based allocation sch...
PDF
Iaetsd adaptive modulation in mimo ofdm system for4 g
PDF
論文-A Novel Cross-layer Mesh Router Placement Scheme for Wireless Mesh Networks
PDF
IRJET-Spectrum Allocation Policies for Flex Grid Network with Data Rate Limit...
PDF
Ijarcet vol-2-issue-7-2277-2280
PDF
IRJET- Design of Low Complexity Channel Estimation and Reduced BER in 5G Mass...
ICICCE0301
PERFORMANCE OF MIMO MC-CDMA SYSTEM WITH CHANNEL ESTIMATION AND MMSE EQUALIZATION
Network efficiency enhancement by reactive channel state based allocation sch...
Iaetsd adaptive modulation in mimo ofdm system for4 g
論文-A Novel Cross-layer Mesh Router Placement Scheme for Wireless Mesh Networks
IRJET-Spectrum Allocation Policies for Flex Grid Network with Data Rate Limit...
Ijarcet vol-2-issue-7-2277-2280
IRJET- Design of Low Complexity Channel Estimation and Reduced BER in 5G Mass...

What's hot (19)

PDF
R33092099
PDF
Load aware self organising user-centric dynamic co mp clustering for 5g networks
PDF
ADAPTIVE RANDOM SPATIAL BASED CHANNEL ESTIMATION (ARSCE) FOR MILLIMETER WAVE ...
PDF
Beam division multiple access for millimeter wave massive MIMO: Hybrid zero-f...
PDF
72 129-135
PDF
200 205 wieser
PDF
LINK-LEVEL PERFORMANCE EVALUATION OF RELAY-BASED WIMAX NETWORK
PDF
Performance evaluation of interference aware topology power and flow control ...
PDF
ADAPTIVE SENSOR SENSING RANGE TO MAXIMISE LIFETIME OF WIRELESS SENSOR NETWORK
PDF
Mitigation of packet loss with end-to-end delay in wireless body area network...
PDF
LARGE-SCALE MULTI-USER MIMO APPROACH FOR WIRELESS BACKHAUL BASED HETNETS
PDF
COMP-JT WITH DYNAMIC CELL SELECTION, GLOBAL PRECODING MATRIX AND IRC RECEIVER...
PDF
5G Coupler Design for Intelligent Transportation System (ITS) Application
PDF
Performance of symmetric and asymmetric links in wireless networks
PDF
Transceiver Design for MIMO Systems with Individual Transmit Power Constraints
PDF
J011137479
PDF
techInvestigations with mode division multiplexed transmission
PDF
80 152-157
PDF
FRAMEWORK, IMPLEMENTATION AND ALGORITHM FOR ASYNCHRONOUS POWER SAVING OF UWBM...
R33092099
Load aware self organising user-centric dynamic co mp clustering for 5g networks
ADAPTIVE RANDOM SPATIAL BASED CHANNEL ESTIMATION (ARSCE) FOR MILLIMETER WAVE ...
Beam division multiple access for millimeter wave massive MIMO: Hybrid zero-f...
72 129-135
200 205 wieser
LINK-LEVEL PERFORMANCE EVALUATION OF RELAY-BASED WIMAX NETWORK
Performance evaluation of interference aware topology power and flow control ...
ADAPTIVE SENSOR SENSING RANGE TO MAXIMISE LIFETIME OF WIRELESS SENSOR NETWORK
Mitigation of packet loss with end-to-end delay in wireless body area network...
LARGE-SCALE MULTI-USER MIMO APPROACH FOR WIRELESS BACKHAUL BASED HETNETS
COMP-JT WITH DYNAMIC CELL SELECTION, GLOBAL PRECODING MATRIX AND IRC RECEIVER...
5G Coupler Design for Intelligent Transportation System (ITS) Application
Performance of symmetric and asymmetric links in wireless networks
Transceiver Design for MIMO Systems with Individual Transmit Power Constraints
J011137479
techInvestigations with mode division multiplexed transmission
80 152-157
FRAMEWORK, IMPLEMENTATION AND ALGORITHM FOR ASYNCHRONOUS POWER SAVING OF UWBM...
Ad

Similar to A wireless precoding technique for millimetre-wave MIMO system based on SIC-MMSE (20)

PDF
Integrating millimeter wave with hybrid precoding multiuser massive MIMO for ...
PDF
Adaptive Random Spatial based Channel Estimation (ARSCE) for Millimeter Wave ...
PDF
Mmse partially connected hybrid beam forming in mimo ofdm
PDF
Mobility and Routing based Channel Estimation for Hybrid Millimeter-Wave MIMO...
PDF
MOBILITY AND ROUTING BASED CHANNEL ESTIMATION FOR HYBRID MILLIMETER-WAVE MIMO...
PDF
An investigation-on-efficient-spreading-codes-for-transmitter-based-technique...
PDF
Enhancing Performance for Orthogonal Frequency Division Multiplexing in Wirel...
PDF
Simulation of Few Mode Fiber Communication System Using Adaptive Recursive le...
PDF
B011120510
PDF
Power saving and optimal hybrid precoding in millimeter wave massive MIMO sys...
PDF
Performance of the MIMO-MC-CDMA System with MMSE Equalization
PDF
Combination of iterative IA precoding and IBDFE based Equalizer for MC-CDMA
PDF
IRJET- MIMO-Energy Efficient and Spectrum Analysis using Congnitive Radio Tec...
PDF
Performance optimization of MIMO-NOMA systems in Nakagami-m fading environments
PDF
Channel Overlapping Between IMT-Advanced Users and Fixed Satellite Service
PDF
Dynamic optimization of overlap
PDF
DYNAMIC OPTIMIZATION OF OVERLAPAND- ADD LENGTH OVER MBOFDM SYSTEM BASED ON SN...
PDF
MULTI USER DETECTOR IN CDMA USING ELLIPTIC CURVE CRYPTOGRAPHY
PDF
TECHNIQUES IN PERFORMANCE IMPROVEMENT OF MOBILE WIRELESS COMMUNICATION SYSTEM...
PDF
Evaluation of massive multiple-input multiple-output communication performanc...
Integrating millimeter wave with hybrid precoding multiuser massive MIMO for ...
Adaptive Random Spatial based Channel Estimation (ARSCE) for Millimeter Wave ...
Mmse partially connected hybrid beam forming in mimo ofdm
Mobility and Routing based Channel Estimation for Hybrid Millimeter-Wave MIMO...
MOBILITY AND ROUTING BASED CHANNEL ESTIMATION FOR HYBRID MILLIMETER-WAVE MIMO...
An investigation-on-efficient-spreading-codes-for-transmitter-based-technique...
Enhancing Performance for Orthogonal Frequency Division Multiplexing in Wirel...
Simulation of Few Mode Fiber Communication System Using Adaptive Recursive le...
B011120510
Power saving and optimal hybrid precoding in millimeter wave massive MIMO sys...
Performance of the MIMO-MC-CDMA System with MMSE Equalization
Combination of iterative IA precoding and IBDFE based Equalizer for MC-CDMA
IRJET- MIMO-Energy Efficient and Spectrum Analysis using Congnitive Radio Tec...
Performance optimization of MIMO-NOMA systems in Nakagami-m fading environments
Channel Overlapping Between IMT-Advanced Users and Fixed Satellite Service
Dynamic optimization of overlap
DYNAMIC OPTIMIZATION OF OVERLAPAND- ADD LENGTH OVER MBOFDM SYSTEM BASED ON SN...
MULTI USER DETECTOR IN CDMA USING ELLIPTIC CURVE CRYPTOGRAPHY
TECHNIQUES IN PERFORMANCE IMPROVEMENT OF MOBILE WIRELESS COMMUNICATION SYSTEM...
Evaluation of massive multiple-input multiple-output communication performanc...
Ad

More from TELKOMNIKA JOURNAL (20)

PDF
Earthquake magnitude prediction based on radon cloud data near Grindulu fault...
PDF
Implementation of ICMP flood detection and mitigation system based on softwar...
PDF
Indonesian continuous speech recognition optimization with convolution bidir...
PDF
Recognition and understanding of construction safety signs by final year engi...
PDF
The use of dolomite to overcome grounding resistance in acidic swamp land
PDF
Clustering of swamp land types against soil resistivity and grounding resistance
PDF
Hybrid methodology for parameter algebraic identification in spatial/time dom...
PDF
Integration of image processing with 6-degrees-of-freedom robotic arm for adv...
PDF
Deep learning approaches for accurate wood species recognition
PDF
Neuromarketing case study: recognition of sweet and sour taste in beverage pr...
PDF
Reversible data hiding with selective bits difference expansion and modulus f...
PDF
Website-based: smart goat farm monitoring cages
PDF
Novel internet of things-spectroscopy methods for targeted water pollutants i...
PDF
XGBoost optimization using hybrid Bayesian optimization and nested cross vali...
PDF
Convolutional neural network-based real-time drowsy driver detection for acci...
PDF
Addressing overfitting in comparative study for deep learningbased classifica...
PDF
Integrating artificial intelligence into accounting systems: a qualitative st...
PDF
Leveraging technology to improve tuberculosis patient adherence: a comprehens...
PDF
Adulterated beef detection with redundant gas sensor using optimized convolut...
PDF
A 6G THz MIMO antenna with high gain and wide bandwidth for high-speed wirele...
Earthquake magnitude prediction based on radon cloud data near Grindulu fault...
Implementation of ICMP flood detection and mitigation system based on softwar...
Indonesian continuous speech recognition optimization with convolution bidir...
Recognition and understanding of construction safety signs by final year engi...
The use of dolomite to overcome grounding resistance in acidic swamp land
Clustering of swamp land types against soil resistivity and grounding resistance
Hybrid methodology for parameter algebraic identification in spatial/time dom...
Integration of image processing with 6-degrees-of-freedom robotic arm for adv...
Deep learning approaches for accurate wood species recognition
Neuromarketing case study: recognition of sweet and sour taste in beverage pr...
Reversible data hiding with selective bits difference expansion and modulus f...
Website-based: smart goat farm monitoring cages
Novel internet of things-spectroscopy methods for targeted water pollutants i...
XGBoost optimization using hybrid Bayesian optimization and nested cross vali...
Convolutional neural network-based real-time drowsy driver detection for acci...
Addressing overfitting in comparative study for deep learningbased classifica...
Integrating artificial intelligence into accounting systems: a qualitative st...
Leveraging technology to improve tuberculosis patient adherence: a comprehens...
Adulterated beef detection with redundant gas sensor using optimized convolut...
A 6G THz MIMO antenna with high gain and wide bandwidth for high-speed wirele...

Recently uploaded (20)

PPTX
Safety Seminar civil to be ensured for safe working.
PPT
Project quality management in manufacturing
PDF
composite construction of structures.pdf
PPTX
Engineering Ethics, Safety and Environment [Autosaved] (1).pptx
PPTX
Artificial Intelligence
PDF
III.4.1.2_The_Space_Environment.p pdffdf
DOCX
573137875-Attendance-Management-System-original
PPTX
Sustainable Sites - Green Building Construction
PDF
The CXO Playbook 2025 – Future-Ready Strategies for C-Suite Leaders Cerebrai...
PDF
Human-AI Collaboration: Balancing Agentic AI and Autonomy in Hybrid Systems
PDF
BMEC211 - INTRODUCTION TO MECHATRONICS-1.pdf
PDF
Operating System & Kernel Study Guide-1 - converted.pdf
PDF
R24 SURVEYING LAB MANUAL for civil enggi
PDF
BIO-INSPIRED HORMONAL MODULATION AND ADAPTIVE ORCHESTRATION IN S-AI-GPT
PDF
TFEC-4-2020-Design-Guide-for-Timber-Roof-Trusses.pdf
PPTX
Internet of Things (IOT) - A guide to understanding
DOCX
ASol_English-Language-Literature-Set-1-27-02-2023-converted.docx
PPTX
M Tech Sem 1 Civil Engineering Environmental Sciences.pptx
PDF
SM_6th-Sem__Cse_Internet-of-Things.pdf IOT
PDF
Automation-in-Manufacturing-Chapter-Introduction.pdf
Safety Seminar civil to be ensured for safe working.
Project quality management in manufacturing
composite construction of structures.pdf
Engineering Ethics, Safety and Environment [Autosaved] (1).pptx
Artificial Intelligence
III.4.1.2_The_Space_Environment.p pdffdf
573137875-Attendance-Management-System-original
Sustainable Sites - Green Building Construction
The CXO Playbook 2025 – Future-Ready Strategies for C-Suite Leaders Cerebrai...
Human-AI Collaboration: Balancing Agentic AI and Autonomy in Hybrid Systems
BMEC211 - INTRODUCTION TO MECHATRONICS-1.pdf
Operating System & Kernel Study Guide-1 - converted.pdf
R24 SURVEYING LAB MANUAL for civil enggi
BIO-INSPIRED HORMONAL MODULATION AND ADAPTIVE ORCHESTRATION IN S-AI-GPT
TFEC-4-2020-Design-Guide-for-Timber-Roof-Trusses.pdf
Internet of Things (IOT) - A guide to understanding
ASol_English-Language-Literature-Set-1-27-02-2023-converted.docx
M Tech Sem 1 Civil Engineering Environmental Sciences.pptx
SM_6th-Sem__Cse_Internet-of-Things.pdf IOT
Automation-in-Manufacturing-Chapter-Introduction.pdf

A wireless precoding technique for millimetre-wave MIMO system based on SIC-MMSE

  • 1. TELKOMNIKA, Vol.17, No.6, December 2019, pp.2782~2789 ISSN: 1693-6930, accredited First Grade by Kemenristekdikti, Decree No: 21/E/KPT/2018 DOI: 10.12928/TELKOMNIKA.v17i6.12802 ◼ 2782 Received December 20, 2018; Revised May 25, 2019; Accepted July 2, 2019 A wireless precoding technique for millimetre-wave MIMO system based on SIC-MMSE Rounakul Islam Boby*1 , Khaizuran Abdullah2 , A. Z. Jusoh3 , Nagma Parveen4 , A. L. Asnawi5 Electrical and Computer Engineering, Kulliyyah of Engineering and International Islamic University Malaysia, Gombak, Selangor, Malaysia, telp: (+603) 6196 4000. *Corresponding author, e-mail: rounaqul2020@gmail.com1 , khaizuran@iium.edu.my2 , azamani@iium.edu.my3 Abstract A communication method is proposed using Minimum Mean Square Error (MMSE) precoding and Successive Interference Cancellation (SIC) technique for millimetre-wave multiple-input multiple-output (mm-Wave MIMO) based wireless communication system. The mm-Wave MIMO technology for wireless communication system is the base potential technology for its high data transfer rate followed by data instruction and low power consumption compared to Long-Term Evolution (LTE). The mm-Wave system is already available in indoor hotspot and Wi-Fi backhaul for its high bandwidth availability and potential lead to rate of numerous Gbps/user. But, in mobile wireless communication system this technique is lagging because the channel faces relative orthogonal coordination and multiple node detection problems while rapid movement of nodes (transmitter and receiver) occur. To improve the conventional mm-wave MIMO nodal detection and coordination performance, the system processes data using symbolized error vector technique for linearization. Then the MMSE precoding detection technique improves the link strength by constantly fitting the channel coefficients based on number of independent service antennas (M), Signal to Noise Ratio (SNR), Channel Matrix (CM) and mean square errors (MSE). To maintain sequentially encoded user data connectivity and to overcome data loss, SIC method is used in combination with MMSE. MATLAB was used to validate the proposed system performance. Keywords: channel matrix, millimetre-wave, minimum mean square error, quantized system, successive interference-cancellation Copyright © 2019 Universitas Ahmad Dahlan. All rights reserved. 1. Introduction The communications in the millimetre wave band suffers from increased path loss exponents, higher shadow fading, blockage and penetration losses, etc., where sub-6 GHz systems leading to a poorer link margin than legacy systems [1-3]. Spatial sparsity of the channel along with the use of large antenna arrays motivates a subset of physical layer beamforming schemes based on directional transmissions for signalling. In this context, there have been a few studies on the design and performance analysis of directional beamforming/ precoding structures for single-user multi-input multi-output (MIMO) systems [4-7]. However, by restricting attention to small cell coverage and by reaping the increased array gains from the use of large antenna arrays at both the base-station and user ends, significant rate improvements can be realized in practice. These works show that directional schemes are not only good from an implementation standpoint but are also robust to phase changes across clusters and allow a smooth trade-off between peak beamforming gain and initial user discovery latency. There has also been progress in generalizing such directional constructions for multi-user MIMO transmissions [8-11]. Several recent works have addressed hybrid beamforming for millimetre wave systems. The problem of finding the optimal precoder and combiner with a hybrid architecture is posed as a sparse reconstruction problem in [12], leading to algorithms and solutions based on basis pursuit methods. While the solutions achieve good performance in certain cases, to address the performance gap between the solution proposed in [12] and the unconstrained beamformer structure, an iterative scheme is proposed in [13, 14] relying on a hierarchical training codebook for adaptive estimation of millimetre wave channels.
  • 2. TELKOMNIKA ISSN: 1693-6930 ◼ A wireless precoding technique for millimetre-wave... (Rounakul Islam Boby) 2783 The authors in [13, 14] show that a few iterations of the scheme are enough to achieve near-optimal performance. In [15], it is established that a hybrid architecture can approach the performance of a digital architecture if the number of RF chains is twice that of the data-streams. A heuristic algorithm with good performance is developed when this condition is not satisfied. Several other works such as [16, 17] have also explored iterative/algorithmic solutions for hybrid beamforming. A common theme that underlies most of these works is the assumption of phase-only control in the RF/analog domain for the hybrid beamforming architecture. This assumption makes sense at the user end with a smaller number of antennas (relative to the base-station end), where operating the PAs below their peak rating across RF chains can lead to a substantially poor uplink performance. On the other hand, amplitude control (denoted as amplitude tapering in the antenna theory literature) is necessary at the base-station end with many antennas for side-lobe management and mitigating out-of-band emissions. Further, given that the base-station is a network resource, simultaneous amplitude and phase control of the individual antennas across RF chains is feasible at millimetre wave base-stations at a low-complexity and cost [18]. The millimetre wave experimental prototype demonstrated in allows simultaneous amplitude and phase control. Table 1 shows the summary of the related review papers. Table 1. Summarization of notable review papers. Methods Years Advantages Disadvantages Conventional mmWave 2016-17 1. High frequency 6GHz. 1. High path loss exponents, 2. higher shadow fading, 3. blockage and penetration losses, etc. Single user MIMO 2013-16 1. Robust to phase changes across clusters and allow a smooth trade-off between peak beamforming gains. Initial user discovery latency. 1. Large antenna arrays motivate a subset of physical layer beamforming. Multi-user MIMO 2014-17 1. Generalizing such directional constructions for multi-user. 1. Switching mode decrease efficiency. 2. Certain data loss. Pursuit methods- based Hybrid architecture. 2014 1. Increased performance by addressing the performance gap between the channel switching. 1. Assumed phase control in the RF/analog domain, only possible in small number of antennae. Digital hybrid architecture. 2016-17 1. Hybrid beamforming. 2. A heuristic algorithm used for better performance. 1. Number of RF chains is twice that of the data-streams. 2. Substantially poor uplink performance. SAPC mmWave 2017 1. Simultaneous amplitude and phase control of the individual antennas across RF chains. 2. Low-complexity and cost. 1. Standard capacity of maximum 127 points. Hybrid precoding single-user mmWave 2017 1. Hybrid precoding/combining is capable. 2. Same performance of the fully digital. 1. Failure of dedicated computer or connection problem can fail the system. 2. Required maintenance. Hybrid precoding for multi-user mmWave 2015 1. Combination of RF combiner and RF beamformer to maximize the channel gain. 2. Derived as a zero-forcing (ZF) precoder. 1. For a small plant. 2. Extension not possible. Mean-squared error (MSE) hybrid precoder 2011 1. Maximum likelihood (ML) decoder and a minimum mean square error (MMSE) decoder. 2. Window coefficients used to generate the quantized values. 1. The performance depends on detection engine. 2. Research Method The proposed system is a combination of successive interference cancellation (SIC) and Minimum Mean Square Error (MMSE) or can be written as SIC-MMSE. In this process, initially, the raw data is sampled and prepared for sub-band packaging according to users’ data symbol. The coder is joined along with MMSE detection system, which will depend upon user or operator. The MMSE detection process will continue to do channel pilot sensing, testing signal quality, estimate the Signal to Noise Ratio (SNR), arrange Channel Matrix (CM) formation, Channel selection & estimation. The MMSE processed data will be filtered for maximum
  • 3. ◼ ISSN: 1693-6930 TELKOMNIKA Vol. 17, No. 6, December 2019: 2782-2789 2784 correlation detection, which is the part of SIC method. This method is used to detect the sequentially processed data according to the users’ symbols and regenerate the data to transfer it through the new channel. While MMSE will constantly monitor the signal quality to realter the channel coefficient, the SIC will help MMSE to improve its performance by fastly processing sequential data so that MMSE can reselect any parameters at any moment to reduce interruption and data loss. At the end of transmission process, the RF modulation will modulate the data then filter with Spectrum Shaping Filter (SSF) and transmit through the channel. A synchronizer is used in transmission process to synchronize any disrupted operation. On the receiver side the signal will be demodulated and reshaped with SSF. After demodulation the same concept of proposed MMSE will be used to decode the data. The synchronizer on the receiver side and transmitter side will be synchronized together through MMSE. Finally, the decoded data will be reframed using same SIC method. This combination (SIC-MMSE) can reduce the channel shortage and performance losses. The total process of proposed system for transmission unit and process of receiver unit are shown in Figure 1. Figure 1. Proposed system approximation for transmission and receiver 2.1. Symbolize Sampling A multiple user with multiple nodes for base station (BS) was considered based on time division duplex (TDD) method where upload and download channel data links consider within coherence interval in a point to point MIMO system. Considering the system have N numbers of nodes on a base station per cells having M number of total antennas per cells and K number of single antennae known as user terminal (UT) in each cell. For K antenna user terminal to base station J can be expressed as: Hjk = Bjk Gjk where, Hjk is the fading’s on J station for K number of single antennae. Bjk is the fading coefficient of large scale and Gjk is the fading coefficient of small scale [7]. Here, Bjk represent path loss and shadow fading of the channel. The matrix was denoted by upper case and bold uppercase used for vector identifications. The Gjk is the total nodal fading effect induced in per cell’s capacity can be represented by [7], Gjk = CM (0, Im) where, C and M are the capacity sum rate & number of BS antennas respectively and Im is the indication function of M. So, H = G√𝐵
  • 4. TELKOMNIKA ISSN: 1693-6930 ◼ A wireless precoding technique for millimetre-wave... (Rounakul Islam Boby) 2785 here, H is channel fading, B represents the large-scale diagonal matrix and G represents the small-scale matrix each column represents a channel from UT to BS. When the number of BS antennas increase the channel, the approximates orthogonal matrix will be lim 𝑛→∞ 𝐻𝐻 𝐻 = B. Each terminal is assigned with a pilot sensing for k number of single antennas, the sensing pilot sk with power equal to, sk,t = [sk1; sk2….skt ]T and at each BS station, ‖𝑠 𝑘 𝑠𝑗 𝐻 ‖2 = 0, if j ≠ k and the transmitted power is equal for all pilots. For the conventional detection the receiver vector matrix y can be denoted by y ∈ CM×1 [8] or y = Hx + n (1) where, C is channel matrix and complex additive white gaussian noise (AWGN) vector, H∈CM×K, x is the symbol vector sent by K user can be denote by x ∈ Ck×1 and number of nodes n. If the symbol error vector e then, e = x - ẋ (2) here, ẋ is the receiving signal. Assuming correlation parameter σ is known perfectly at the base stations and h[n] be the channel vector between a UT and a BS at time t. Then [9], h[t] = σ h [t - 1] + ev[t] (3) here, t is time index and e[t] is white noise with zero mean and temporal correlation parameter σ2 obtained through the Yule-Walker equation [7]. The channel model above is known as the stationary ergodic Gauss-Markov block fading channel model [8]. 2.2. MMSE Detection Process For the MIMO model equation according to reference no [7], where receiving signal vector ŷ from receiver signal y and the fibrinous norm ‖𝑦‖2 to limit sphere of validity of general norm. ŷ = y − H ẋ = H (e + x) (3) where, x is transmitted symbol massages and ẋ is the received symbol massages. Error vector e should be zero for ideal communication system. So, that the error detection should be overcome from receiver signal vector. Some researcher expresses the compressing sensing methods, where they proposed to naturally consider the symbol error vector e [7]. In compressing sensing methods M should be less then K, but if M becomes more then equal to K, this system will be impractical. For MIMO multi-antenna mode, the M is generally greater then equal K, the receiver signal vector later filter by matrix WMMSE is given by: WMMSE = = 𝐻ℎ 𝐻 𝐻ℎ +𝐼 𝑚 (4) where, W is a predefine filter matrix, WMMSE is the filter matrix for MMSE matrix for and AWGN (Gaussian noise) vector n ∈ CM for CM (0, Im) [8]. By Maximum A Posterior (MAP) detection known as detection system detection method the optimal detection é can be found from the reference paper no [10]. é ≅ arg max 𝑒∈ ˆA 𝐾 (1 √2𝜋𝜎2⁄ ) exp [ −0.707 𝜎2 ((||ŷ − He||)2 2 ] Pr(e) (5) According to the paper the approximation is because of e and n dependency and may omit while SNR increases and can be precise at high SNRs [10]. Pr(e) is probability of priority error symbol. When BPKS values are +1 & -1, ˆA is the finite alphabet having the values -2, 0 & +2 and for the nonzero value of A´ detection error becomes -2 & 2. If transmitted symbols are from -1 to 1, then the possibility of the e will be no zeroes from +2 to -2 and possible probability
  • 5. ◼ ISSN: 1693-6930 TELKOMNIKA Vol. 17, No. 6, December 2019: 2782-2789 2786 can be 0.5P. When λ is the degree of sparsity, ||e||= 0.25||e||2 . If, e is the element of ˆA 𝐾 and e is the symbol error vector for initial iteration, by solving (5): e= HHˆy HHH+0.5 λ e= 𝑀ˆy; [if, ˆA 𝐾 is finite and initially é= e] (6) here, M is MMSE detection method with tuneable degree of sparesλ, where, λ is the replacement of noise. If, Qθ(*) is vector dividing function and θ optimal threshold then, optimal detection, é=Qθ(e) for discrete function [10]. So, we can rewrite: é = Qθ(e) = 2sin(e)I ; [||e||>θ] (7) where, “I” is the indication function. If, the optimal threshold, θ = {θ1, θ2, θ3, …, θn} and for the non-zero components, e = {0, ±2}; [i.e. ||e||<θ]. Similarly, QPSK detection the equivalent transform with real (R) and imaginary (I), where I(e) and R(e) parts of x, é = 2sin [ {R(e) + I(e)} T]; [Where, e ˆA ] (8) here, y initial receiver signals, n is the Gaussian noise, e(l) is the lth symbol error vector. (8) is the prior probability detection of e. If, e(l) is non-zero, for the nth entry, 𝑥 𝑛 𝑙−1 is of 𝑥 𝑙−1 , the 𝑦 for nth entry of lth symbol, 𝑦 𝑛 𝑙 = W(l−1) 𝑒 𝑛 𝑙 +∑ 𝑤 𝑛𝑗 1−𝑙 𝑖≠𝑗 𝑒𝑗 𝑙 + 𝑥 𝑛 𝑙−1 (9) so, Gaussian approximates with following variance𝜎, (𝜎 𝑛 𝑙−1 )2 = ∑ 4(𝜔𝑗𝑛 1−𝑙 )2 𝑝𝑙−1 + {∑ (𝑙 − 1)𝑛 𝑛 𝑛≠𝑗 } (10) 2.3. SIC Algorithm Considering the mm-wave MIMO system with Distributed Antenna System (DAS) configuration, where, number of base antenna MB having k number of single antenna and N number remote radio heads. If the Q user also equipped with MU antenna, the receiving antennas, MR = MB + Nk ≥ QMU [19-26]. For Q user MU number flat fading channels, the MMSE pilot sk was considered before now can be rewritten as vectoral form, sk ∈ CM u ×1. From the model as Gauss-Markov block fading channel shown above in (3), the data vector sk have zero mean. The SIC algorithm relies on sequential detection receiver signals, where it is required to equalize the channel matrices WMMSE given in (4), then carrier channels can get the higher Signal to Interference Noise Ratio (SINR). From the reference no [26] the SINR per symbol for Ith iteration for the jth number of symbols is thus can be expressed as, 𝑆𝐼𝑁𝑅 𝑗 𝑖 = (𝜎 𝑖 )−2 (𝑎𝑖 )2 (|ski|)2 (13) where, 𝑎𝑖 is the amplitude, Gaussian approximates variance𝜎, pilot sk for Ith iteration. The fading matrix Hk for k user, having N+1 submatrix in each remote radio head, then, Hk = [Hk1, Hk2, …, Hk(N+1)]T. When the symbol is decides according a decision will be made depends on MMSE operator given in (11). Instead of executing don’t care sign decision, it is possible to use operator Q as soft switch through the hyperbolic tangent non-linear detector whose argument is weighted by an estimation of the SINR [26]. So, the expression for sk for Ith iteration can be given in QPSK constellation as, 𝑠 𝑘𝑖 = 0.707 [tanh{𝑅(𝑦 𝑘𝑖)/(𝜎𝑘𝑖 2 )} + 𝑗 tanh{𝐼(𝑦 𝑘𝑖)/(𝜎𝑘𝑖 2 )}] (14) finally, for the decoded case in receiver end, while all symbols are retrieved, the don’t care decision will perform for the resulting output y = (y1, y2, …, yn)T.
  • 6. TELKOMNIKA ISSN: 1693-6930 ◼ A wireless precoding technique for millimetre-wave... (Rounakul Islam Boby) 2787 3. Measurement and Simulations For MATLAB simulation we used Gaussian noise as reference with different SNR levels to analyse the performance of the proposed SIC-MMSE system. In this simulation process we have compared results with conventional mm-wave MIMO system and MMSE system. For the simulation process we first considered the number of antennae per cells M=1000. For the process, initially we detected symbol vector j using conventional MIMO system and proposed MMSE. For the output SNRs priority probability for conventional and MMSE we followed equations from the reference papers [7-10] shown in (15): lim 𝑆𝑁𝑅→∞ log 𝑃𝑐 (𝑆𝑁𝑅) log 𝑆𝑁𝑅 = −𝑑; lim 𝑆𝑁𝑅→∞ log 𝑃 𝑆𝐼𝐶−𝑀𝑀𝑆𝐸 (𝑆𝑁𝑅) log 𝑆𝑁𝑅 = −𝑑 (15) Then, the degree of sparsity λ, can be obtained from λ=ln[ 2(1−𝑝) 𝑝 ]; Considering the MMSE linear detection, for the Ith iteration the error probability é for SIC-MMSE based MIMO was obtained from (8), where optimal threshold 𝜃 𝑛 𝑙 was obtained by solving the (7). This proposed research was conduct on Time Division Duplex (TDD) method. So, to determine the Spectral Efficiency (SE) for SIC-MMSE is expressed [27]: ηhMMSE = (𝑇 𝑓− 𝑇 𝑝 − 𝑇𝑡)𝑁 𝑖 𝑇 𝑖 𝑁 𝑠 (16) where Tp = preamble period, Tt = trailer time period, Tf = frame duration and Ns = number of symbols in a t time slot, Ni = number of information bits. By resoliving the equations in MATLAB finally we got SE for the SIC-MMSE. Simulating the proposed system in MATLAB the performance of SIC-MMSE was achieved. For the comparison and benchmarking we also simulated the conventional mm-Wave, where the simulation was done by Spectral Efficiency (SE) [bit/s/Hz/cell] vs Number of BS Antennas (M). Figure 2 shows the comparison of the Spectral Efficiency (SE) with the increase number of BS antenna at base station for conventional or single millimetre-Wave system, where it is depicted that spectral efficiency increases from 0 to maximum 136 bits/s/Hz/cell with the increase of base antennas from 0 to 1000. Where, the parameters are optimized for the better performance, the maximum SE was recorded to 157 bits/s/Hz/cell for the 1000 number of antennas. Figure 2. Conventional mm-waves MIMO and optimized mm-waves MIMO spectral efficiency performance with the increase number of Antennas. The SIC-MMSE simulation in Figure 3 shows better performance than conventional mm-Wave MIMO system after optimization. Before optimization the maximum SE was found to 133~132 bits/s/Hz/cell while number of antennas was maximum. Where, after optimization
  • 7. ◼ ISSN: 1693-6930 TELKOMNIKA Vol. 17, No. 6, December 2019: 2782-2789 2788 the value crossed 195 bits/s/Hz/cell. Every system requires optimization, where this proposed system performed almost the equal to optimized conventional mm-wave MIMO system, but after optimization it rapidly increased. Figure 4 shows the performance comparison simulation block for the both methods having same parameters, spectral efficiency according to increase number of antennas. Figure 3. Proposed SIC-MMSE and optimized SIC-MMSE spectral efficiency performance according to increase number of antennas Figure 4. The performance of both methods’ spectral efficiency according to increase number of antennas 4. Conclusion and Future Work This paper has presented a communication method which is the combined methodology of MMSE and SIC technique for mm-Wave MIMO based wireless communication system. The combined method was proposed to reduce the relative orthogonal coordination and multiple node detection problem while transmitter or receiver moves. The development of the equations was done by comparing, reading and reoptimizing the existed several concepts. From the simulation it can found that, the proposed combined technique for wireless power communication is better than conventional mm-wave MIMO. Though, the Proposed SIC-MMSE require optimization for better performance more combined technique with better optimization can lead a better performance then single one. In future we would like to improve this research by adding more system together for optimal performance and compare with recent research. 5. Acknowledgements This paper was part of works conducted under the IIUM Research Initiative Grant Scheme (RIGS16-334-0498 & RIGS17-031-0606). The authors would also like to acknowledge all supports given by the IIUM Research Management Centre through the grant and RAY R&D for their research support. References [1] Aalto University, AT&T, BUPT, CC, Ericsson, Huawei, Intel, KT Corporation, Nokia, NTT DOCOMO, NYU, Qualcomm, Samsung, U. Bristol, and USC. White paper on 5G channel model for bands up to 100 GHz. 2016 Oct. v2.3. [2] Sun S, Rappaport TS, Thomas TA, Ghosh A, Nguyen HC, Kovács IZ, Rodriguez I, Koymen O, Partyka A. Investigation of prediction accuracy, sensitivity, and parameter stability of large-scale propagation path loss models for 5G wireless communications. IEEE Transactions on Vehicular Technology. 2016; 65(5): 2843-60. [3] Raghavan V, Partyka A, Akhoondzadeh-Asl L, Tassoudji MA, Koymen OH, Sanelli J. Millimeter wave channel measurements and implications for PHY layer design. IEEE Transactions on Antennas and Propagation. 2017; 65(12): 6521-6533. [4] Rusek F, Persson D, Lau BK, Larsson EG, Marzetta TL, Edfors O, Tufvesson F. Scaling up MIMO: Opportunities and challenges with very large arrays. arXiv preprint arXiv: 1201.3210. 2012.
  • 8. TELKOMNIKA ISSN: 1693-6930 ◼ A wireless precoding technique for millimetre-wave... (Rounakul Islam Boby) 2789 [5] Roh W, Seol JY, Park J, Lee B, Lee J, Kim Y, Cho J, Cheun K, Aryanfar F. Millimeter-wave beamforming as an enabling technology for 5G cellular communications: Theoretical feasibility and prototype results. IEEE communications magazine. 2014; 52(2): 106-113. [6] Raghavan V, Subramanian S, Cezanne J, Sampath A, Koymen OH, Li J. Single-user versus multi-user precoding for millimeter wave MIMO systems. IEEE Journal on Selected Areas in Communications. 2017; 35(6): 1387-1401. [7] Anderson CR, Rappaort TS. In-Building Wideband Partition Loss Measurements at 2.5 GHz and 60 GHz. arXiv preprint arXiv: 1701.03415. 2016. [8] Raghavan V, Cezanne J, Subramanian S, Sampath A, Koymen O. Beamforming tradeoffs for initial UE discovery in millimeter-wave MIMO systems. IEEE Journal of Selected Topics in Signal Processing. 2016; 10(3): 543-559. [9] Sun S, Rappaport TS, Heath RW, Nix A, Rangan S. MIMO for millimeter-wave wireless communications: Beamforming, spatial multiplexing, or both?. IEEE Communications Magazine. 2014; 52(12): 110-121. [10] Raghavan V, Subramanian S, Cezanne J, Sampath A, Koymen O, Li J. Directional hybrid precoding in millimeter-wave MIMO systems. 2016 IEEE Global Communications Conference (GLOBECOM). 2016: 1-7. [11] Ran R, Wang J, Oh SK, Hong SN. Sparse-aware minimum mean square error detector for MIMO systems. IEEE Communications Letters. 2017; 21(10): 2214-2217. [12] Khaizuran A, Rounakul IB. SIC-MMSE Method based Wireless Precoding Technique for Millimetre-Wave MIMO System. Indian Journal of Science and Technology. 2019: 12(9): 1-11. [13] Wang Z, Li M, Liu Q, Swindlehurst AL. Hybrid precoder and combiner design with low-resolution phase shifters in mmWave MIMO systems. IEEE Journal of Selected Topics in Signal Processing. 2018; 12(2): 256-269. [14] El Ayach O, Rajagopal S, Abu-Surra S, Pi Z, Heath RW. Spatially sparse precoding in millimeter wave MIMO systems. IEEE transactions on wireless communications. 2014 Mar; 13(3): 1499-1513. [15] Venugopal K, Alkhateeb A, Prelcic NG, Heath RW. Channel estimation for hybrid architecture-based wideband millimeter wave systems. IEEE Journal on Selected Areas in Communications. 2017; 35(9): 1996-2009. [16] Alkhateeb A, Leus G, Heath RW. Limited feedback hybrid precoding for multi-user millimeter wave systems. IEEE transactions on wireless communications. 2015; 14(11): 6481-6494. [17] Sohrabi F, Liu YF, Yu W. One-bit precoding and constellation range design for massive MIMO with QAM signaling. IEEE Journal of Selected Topics in Signal Processing. 2018; 12(3): 557-570. [18] Sadeghi M, Björnson E, Larsson EG, Yuen C, Marzetta TL. Max–min fair transmit precoding for multi-group multicasting in massive MIMO. IEEE Transactions on Wireless Communications. 2018; 17(2): 1358-1373. [19] Noh S, Zoltowski MD, Love DJ. Training sequence design for feedback assisted hybrid beamforming in massive MIMO systems. IEEE Transactions on Communications. 2016; 64(1): 187-200. [20] Russell DS, Fischer LG, Wala PM. Cellular communications system with centralized base stations and distributed antenna units. US 5,657,374 (Patent). 1997. [21] Ortega AJ, Sampaio-Neto R. Random-Multi-Branch Successive Interference Cancellation detection in single-user and multi-user MIMO environments. [22] Roh W, Paulraj A. MIMO channel capacity for the distributed antenna. Proceedings IEEE 56th Vehicular Technology Conference. 2002; 2: 706-709. [23] Zhuang H, Dai L, Xiao L, Yao Y. Spectral efficiency of distributed antenna system with random antenna layout. Electronics Letters. 2003 20; 39(6): 495-496. [24] Castanheira D, Gameiro A. Distributed antenna system capacity scaling [coordinated and distributed mimo]. IEEE Wireless Communications. 2010; 17(3): 68-75. [25] Shida M. Distributed antenna system. United States patent US 8,923,908. 2014. [26] Debbah M, Muquet B, De Courville M, Muck M, Simoens S, Loubaton P. A MMSE successive interference cancellation scheme for a new adjustable hybrid spread OFDM system. VTC2000-Spring 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No. 00CH37026). 2000; 2: 745-749.