High Speed Packet Access

ACKNOWLEDGEMENT
We take this opportunity to express my profound sincere gratitude to all those who
helped us to carry out this project successfully.
We owe our sincere gratitude to our Principal, Mr.D.Prasad and also to our
committee members for giving the encouragement that helped us to complete the project
successfully
At the very outset we convey our gratitude to Mr.L.Praveen Kumar, HOD, and
ECE for allotting us this project and enabling us to complete the seminar successfully. We
express our profound gratitude for his valuable guidance and support.
Our sincere thanks to Mr.D.Prasad, Associate professor of ECE,
RAMANANDATIRTHA ENGINEERING COLLEGE who inspired with her valuable
suggestions and advice throughout our project work. We also express sincere thanks to all
other staff members.
We here by thank one and all who extended helping hand in the accomplishment of
the technical report.

TABLE OF CONTENTS
NAME OF THE CHAPTER PAGE N.O
ABSTRACT ii
LIST OF FIGURE iii
BRIEF IDEA 1
1.INTRODUCTION
1.1 WHAT IS HSPA 3
1.2 MECHANISAM 4
2.HSDPA 5
2.1 HIGH-SPEED SHARED CHANNELS AND
SHORT TRANSMISSION TIME INTERVAL 7
2.2 FAST SCHEDULING AND USER DIVERSITY 7
2.3 HIGHER ORDER MODULATION 8
2.4 FAST LINK ADAPTATION 8
2.5 FAST HYBRID AUTOMATIC REPEAT REQUEST 9
2.6 MECHANISM 10
3.HIGH-SPEED UPLINK PACKET ACCESS 14
3.1 HIGH-SPEED UPLINK PACKET ACCESS 13
4.EVOLVED HSPA 17
4.1 EVOLVED HSPA 17
5.ADVANTAGES 19
6.DISADVANTAGES 20
7.APPLICATIONS
8.FUTURE SCOPE 21
9.CONCLUSION 22
REFERENCES 23
i

ABSTRACT
The High Speed Packet Access technology is the most widely used mobile
broadband technology in communication world. It was already built in more than 3.8
billion connection with GSM family of technologies. The HSPA technology is referred to
both High Speed Downlink Packet Access (3GPP Release 5) and to High Speed Uplink
Packet Access (3GPP Release 6). The Evolved HSPA technology or HSPA + is the
evolution of HSPA that extends operator’s investments before the next generation’s
technology 3GPP Long Term Evolution (LTE or 3GPP Release 8). The HSPA technology
is implemented on third generation (3G) UMTS/WCDMA network and accepted as the
leader in mobile data communication.
Using the HSDPA optimization on downlink is performed, whereas the HSUPA
technology applying Enhanced Dedicated Channel (E-DCH) sets some improvements for
the uplink performance optimization. The products that support HSUPA became available
in 2007 and the combination of both HSDPA and HSUPA were called HSPA. Adopting
these technologies the throughput, latency and spectral efficiency were improved.
Introducing HSPA resulted to the increase of overall throughput approximately to 85 % on
the uplink and a rise more than 50 % in user throughput. The HSPA downlink available
rates are 1 to 4 Mbps and for the uplink are 500 kbps to 2Mbps as of 1 quarter of 2009. The
theoretical bit rates are 14Mbps at the downlink and 5.8 Mbps at the uplink in a 5MHz
channel. Besides, the latency is notably reduced as well. In the improved network, the
latency is less than 50ms, and after the introduction of 2ms Transmission Time Interval
(TTI) latency is expected to be just 30ms.
ii

LIST OF FIGURES
NAME OF THE FIGURE PAGE N.O
1.Figure 1.2.1new UMTS Radio Network Protocol Architecture 4
2.Figure 2.1.1 Different Users Obtaining Different Radio Resources 7
3.Figure 2.2.1 Signal Quality 8
4.Figure 2.6.1 Simplified HSDPA Transmission Scheme 11
5.Figure 3.1 Data and Signal Flow 16

BRIEF IDEA
They made GSM modems. Does anyone remember the times we used those horrible 56K
modems to connect your desktop to the internet by plugging it into your phone line? Well
at first that’s how they did it with mobile phones in a roughly similar way too! Very low
data rates of 10kbps and also the fact that you paid for the time you used the service were
the main down points of this.
2-GENARATION:
However, with the take up on mobile phones rapidly increasing we saw the switch
to digital networks which allowed for better call quality and the SMS service. We started
to see the potential for data to be sent using them. 2G was born in the form of GPRS. This
allowed data to be sent over a network that was a lot more optimized for data
communication.
GPRS was and still is a little bit slow at no more than about 114kbps and unless
you have a class 3 device, it can’t support sending data at the same time as a GSM voice
call is in session. However this is more than enough for many people’s needs, even today
and to add weight to that, the first iPhone was a GPRS device.
EDGE A STOP-GAP:
3G was on the way but we saw one more incremental step before this was rolled
out. Edge, eGPRS or 2.5G was a technology that gave us 3 fold better data rates with
typical 400kbps being heralded by Cingular in the USA by using better coding methods
than GPRS. However 120-200kbps is probably more realistic.
FINALLY 3G ARRIVES:
Finally full 3G was released and it not only gave us more reliable faster data rates
of up to 384kbps but it’s based upon a far better better platform that allows synchronous
voice and data usage. With 3G browsing the web performing more media intensive data
work became a reality and in some cases still rivals some broadband connections we have
in our homes

HSDPA AND 3.5G, 3.75, 4G AND BEYOND:
Currently HSDPA is the standard for most mobile phones. Running at 1.3mbps it
rivals most broadband connections and networks are being upgraded across the UK to run
at speeds of up to 7.2mbps, coined 4G.
We’re now even starting to see our first 4G devices in the HTC 4G MAX, although
we’re actually seeing a trend in 3.75G HSUPA devices being released at the moment,
which are actually HSDPA devices but with improved upload speeds too.
Added (19/10/11) HSPA is it a spelling mistake!
Well no and HSPA and also evolved HSPA or HSPA+ are all new acronyms in the
3G world. I’m not going to get technical here, but these protocols are basically the next
step in the mobile networks upgrade path. HSPA (Download) and HSUPA (Upload) are
pretty much implemented now and devices taking advantage of this can now theoretically
reach speeds of 14MBPs on the downlink and 6MBPS up, some networks in the world
have reported even more than this. HSPA+ further enhances this up to 80 & 22 MBPS
which is now surpassing broadband speeds.
With 3.5G, 3.75G, 4G and now HSPA we really now have no excuse to be connected
to the Internet where-ever we go and its only a matter of time before the PDA or mobile
phone truly becomes the data tool of choice as our lives become ever mobile.

1. INTRODUCTION
1.3 WHAT IS HSPA:
HSPA - High Speed Packet Access is the most widely deployed mobile broadband
technology in the world today and will build upon the more than 5 billion connections with
the GSM family of technologies. HSPA builds on third generation (3G)
UMTS/WCDMA and is strongly positioned as the leading mobile data technology for the
foreseeable future.
By now UMTS is a well-established technology with manifold networks running
globally and competitive terminals on the market. A significant shift from traditional
circuit-switched, often constant bit-rate services to IP packet switched services is expected
in the near future. UMTS Release 99, based on dedicated resource allocation per user, is
not well suited for IP packet data traffic. Therefore High Speed Packet Downlink Access
(HSDPA) and Enhanced Dedicated Channel (E-DCH) have been introduced as new
features of UMTS for Downlink and Uplink in UMTS Release 5 and Release 6,
respectively. This technology called High Speed Packet Access (HSPA) claims significant
enhancements in end-to-end service provisioning for IP based services. This introduces
these future technology enhancements and assesses the potential gains for future
applications and in term user perception
Bulleted Points
 HSDPA (3GPP Release 5)
 HSUPA (3GPP Release 6)
 Both technologies are deployed on a network.
 HSPA Evolved (HSPA+ in 3GPP Release 7 and beyond) is also part of the HSPA
technology.
 HSPA claims significant enhancements in end-to-end service provisioning for IP
based services.

1.2 MECHANISM:
In addition to the paradigm change from using dedicated resources to making use
of shared radio resources, the main technology changes introduced are:
 Fast Node B scheduling with adaptive coding and modulation (only downlink) to
exploit the varying radio channel and interference variations and accommodate
bursty IP traffic,
 No
de B based Hybrid ARQ to reduce retransmission round trip times and add
robustness to the system by allowing soft combining of retransmissions,
 Reduced transmission time interval (TTI) for latency reduction and to support fast
scheduler decisions and quick HARQ retransmissions.
 These added functionalities have been specified in several new MAC sub-layers
and modifications of the physical layer as is depicted in Figure 1.
In general retransmissions are now performed directly between Node B and the User
equipment (UE). This reduces latency and saves resources on the Iub interface. The
distributed scheduling performed by RNC and Node B requires an additional scheduling
buffer in the Node B as well as having an additional flow control on the Iub interface.
Furthermore, the Node B needs to be made aware of certain QoS parameter to ensure that
the data transmission complies with the traffic requirements.

Nevertheless, HSDPA and HSUPA can be implemented in the standard 5 MHz
carrier of UMTS networks and can co-exist with the existing 3GPP Release 99 networks.

2. HSDPA: High Speed Downlink Packet Access
HSDPA (High Speed Downlink Packet Access) is an upgrade to UMTS/WCDMA.
HSDPA increases the download speeds by up to 3.5 times, initially delivering typical user
data rates of 550 to 800 kbps. Improvements to the downlink, through HSDPA, were the
first upgrade steps available to operators seeking to deploy mobile broadband services as a
part of 3GPP Release 5. There is some confusion regarding the use of acronyms involving
HSDPA, and its further evolution to High Speed Uplink Packet Access (HSUPA), as the
terms are often used interchangeably along with the acronym HSPA which refers to the
both HSDPA and HSUPA in their evolved state.
HSDPA speeds are ideal for bandwidth-intensive applications, such as large file
transfers, streaming multimedia and fast Web browsing. HSDPA also offers latency as low
as 70 to 100 milliseconds (ms) making it ideal for real-time applications such as interactive
gaming and delay-sensitive business applications such as Virtual Private Networks
(VPNs).
High Speed Downlink Packet Access is predominately a software upgrade to
Release 99 of the UMTS standard. HSDPA has been commercially available since
December 2005, when Cingular Wireless – now AT&T – launched the world's first large
scale HSDPA service. There are more than 400 HSDPA networks commercially deployed
or in various stages of deployment. International roaming is available as the technology
falls back on UMTS, EDGE and GPRS for the continuation of voice and data services.
HSDPA usually requires only new software and base station channel cards, instead
of necessitating the replacement of major pieces of infrastructure from UMTS and does not
require additional spectrum for deployment. As a result, UMTS operators can deploy
HSDPA quickly and cost-effectively. In fact, most operators that deploy UMTS are
deploying an HSDPA-ready network.
HSDPA technology significantly improves the UMTS downlink performance
through techniques, such as adaptive modulation and coding, hybrid ARQ (HARQ) and
fast scheduling.

On the receiving side, initial HSDPA User Equipment (UE) solutions were based
on single antenna CDMA rake receiver structures, similar to Release 99 UMTS receiver
structures. The corresponding minimum performance requirement for HSDPA rake
receivers was specified in Release 5. While the single antenna rake, receivers worked very
well for conventional UMTS and met initial system needs for HSDPA, advanced receiving
technologies were later used to achieve even higher HSDPA throughputs. To achieve this
goal, 3GPP studied two applicable techniques (receive diversity and advanced receiver
architectures) as well as their minimum performance improvement and has specified them
in Release 6.
HSDPA also benefits operators by making more efficient use of spectrum, up to
three times more capacity than UMTS. This efficiency means that operators can easily and
cost-effectively accommodate more users and services without having to buy additional
spectrum just to keep up with growth. That efficiency also reduces operators' overhead
costs, and thus, makes them better able to price their services at a point that is competitive
yet profitable.
HSDPA is backward-compatible with UMTS, EDGE and GPRS. This design
benefits customers when they travel to areas that have not yet been upgraded to HSDPA,
as their HSDPA-enabled handsets and modems will still provide fast packet-data
connections. This design also benefits operators and application developers because
applications designed for UMTS also run on HSDPA networks and devices.
HSDPA achieves its performance gains from the following radio features:
2.1 High-speed channels shared in both code and time domains
2.2 Short TTI
2.3 Fast scheduling and user diversity
2.4 Higher order modulation
2.5 Fast link adaptation
2.6 Fast HARQ

2.1HIGH-SPEED SHARED CHANNELS AND SHORT
TRANSMISSION TIME INTERVAL:
First, HSDPA uses high-speed data channels called High Speed Physical Downlink
Shared.
Channels (HS-PDSCH). Up to 15 of these channels can operate in the 5 MHz
WCDMA radio channel. Each uses a fixed spreading factor of 16. User transmissions are
assigned to one or more of these channels for a short TTI of 2 ms, significantly less than
the interval of 10 to 20 ms used in Release 99 WCDMA.
The network can then readjust how users are assigned to different HS-PDSCH every 2
msec. The result is thatresources are assigned in both time (the TTI interval) and code
domains (the HS-PDSCH channels).
Figure
2.1.1
Different Users Obtaining Different Radio Resources
2.2 FAST SCHEDULING AND USER DIVERSITY:
Fast scheduling exploits the short TTI by assigning users channels that have the
best instantaneous channel conditions rather than in a round-robin fashion.

Because channel conditions vary somewhat randomly across users, most users can
be serviced with optimum radio conditions and thereby obtain optimum data throughput.
Figure 3shows how a scheduler might choose between two users based on their
varying radio conditions to emphasize the user with better instantaneous signal quality.
With about 30 users active in a sector, the network achieves significant user diversity and
significantly higher spectral efficiency. The system also makes sure that each user receives
a minimum level of throughput. This approach is sometimes called proportional fair
scheduling.
Figure 2.2.1 Signal Quality
2.3 HIGHER ORDER MODULATION:
HSDPA uses both the modulation used in WCDMA—namely QPSK—and, under
good radio conditions, an advanced modulation scheme—16 QAM.
The benefit of 16 QAM is that 4 bits of data are transmitted in each radio symbol
as opposed to 2 bits with QPSK. Data throughput is increased with 16 QAM, while QPSK
is available under adverse conditions. HSPA Evolution will add 64 QAM modulation to
further increase throughput rates.

2.4 FAST LINK ADAPTATION:
Depending on the condition of the radio channel, different levels of forward-error
correction (channel coding) can also be employed.
For example, a three-quarter coding rate means that three quarters of the bits
transmitted are user bits and one quarter is error-correcting bits.
The process of selecting and quickly updating the optimum modulation and coding
rate is referred to as fast link adaptation. This is done in close coordination with fast
scheduling, as described above.
2.5 FAST HYBRID AUTOMATIC REPEAT REQUEST:
Another HSDPA technique is Fast Hybrid Automatic Repeat Request (Fast Hybrid
ARQ). “Fast” refers to the medium-access control mechanisms implemented in Node B
(along with scheduling and link adaptation), as opposed to the BSC in GPRS/EDGE, and
“hybrid” refers to a process of combining repeated data transmissions with prior
transmissions to increase the likelihood of successful decoding. Managing and responding
to real-time radio variations at the base station, as opposed to an internal network node,
reduces delays and further improves overall data throughput.
Using the approaches just described, HSDPA maximizes data throughputs and
capacity and minimizes delays. For users, this translates to better network performance
under loaded conditions, faster application performance, a greater range of applications
that functions well, and increased productivity.
Field results validate the theoretical throughput results. Using 1.8 Mbps peak-rate
devices, vendors have measured consistent throughput rates in actual deployments of over
1 Mbps. These rates rise to over 2 Mbps for 3.6 Mbps devices and to close to 4 Mbps for
7.2 Mbps devices, assuming other portions of the network (for example, backhaul) can
support the high throughput rates.
Initial HSDPA devices had peak rates of 1.8 Mbps.78 By the second half of 2006, users
were able to purchase both HSDPA handsets and data cards supporting peak network rates
of 3.6 Mbps. In 2007, devices with peak data rates of 7.2 Mbps became available. Many
operator networks support 3.6 Mbps peak operation, and some even support the maximum
rate of 14.4 Mbps.

The attraction of HSDPA is that it is fully compatible with WCDMA Release 99
and can be deployed as a software-only upgrade to newer WCDMA networks. This
approach has already proven extremely effective with GPRS upgrades to EDGE. HSDPA,
which uses many of the same proven radio techniques that EDGE applied to GPRS, is
essentially the same approach applied to WCDMA.
WCDMA Release 99 provided the initial foundation, while HSPA, and later
HSPA+, unleashes the full inherent potential of the radio channel. The market has
responded enthusiastically to HSDPA. By July 2007, there were 311
different HSDPA-capable handsets and devices, including 137 mobile phones, 64 PC data
cards, 23 USB modems, 51 notebooks with embedded HSDPA capability, 32 wireless
routers, three media players, and one camera and the technology is not standing still.
Advanced radio technologies are becoming available. Among these technologies are
mobile-receive diversity and equalization (for example, MMSE), which improve the
quality of the received radio signal prior to demodulation and decoding. This improvement
enables not only higher peak HSDPA throughput speeds but makes these speeds available
over a greater percentage of the coverage area.
2.6 MECHANISM:
In downlink a new entity called MAC-hs contains the new HSDPA functionality as
seen in Figure 1. Instead of a fixed code allocation with fast power control, the code and
power resource is now shared amongst all active HSDPA users. For this purpose a new
transport channel, the High Speed Downlink Shared Channel (HS-DSCH), has been
defined that supports adaptive coding and modulation, whereby every 2ms the transmission
format can change dynamically.
In good radio channel condition 16QAM modulation can be used instead of QPSK
and the rate 1/3 turbo code may be punctured down to enable higher data rates. Depending
on the UE capabilities up to 15 codes with a fixed spreading factor of 16 can be received
if all codes are allocated to a single UE. Since power control is replaced by rate control
with adaptive coding and modulation the maximum data rate as received by the user
directly depends on the channel and interference conditions as well as the user position in
the cell.

The Node B scheduler must take care that fairness is maintained. The dynamic
resource allocation by the scheduler (per 2ms TTI) is signaled to the users on a new
downlink control channel called High Speed Signaling Control Channel (HS-SCCH).
The following information is carried on the HS-SCCH:
 UE Identity (UE ID) via a UE specific CRC which allows addressing specific UEs
on the shared control channel.
 Transport Format and Resource Indicator (TFRI) which identifies the scheduled
resource and its transmission format.
 Hybrid-ARQ-related information to identify redundancy versions for the
combining process.
 Each user can monitor up to 4 HS-SCCHs. For the support of channel based
scheduling and HARQ the following feedback signaling is transmitted on the High
Speed Dedicated Physical Control Channel (HS-DPCCH) in the uplink:
 Channel Quality Information (CQI) to inform the scheduler about the instantaneous
channel
 condition.
 HARQ ACK/NACK information to let the sender know the outcome of the
decoding process and to request retransmissions
Figure 2.6.1 Simplified HSDPA Transmission Scheme
Figure depicts the data and signaling flow during HSDPA transmission. Based on
the UE channel quality report the Node B scheduler sends data on the shared downlink
channel to the user.

The UE will then reply with an ACK or NACK message based on the outcome of
the decoding. Note that the standard does not specify scheduling and resource allocation
which leaves significant freedom to Node-B implementations.

3.HIGH-SPEED UPLINK PACKET ACCESS (HSUPA)
3.1 High-Speed Uplink Packet Access (HSUPA):
Whereas HSDPA optimizes downlink performance, HSUPA—which uses the Enhanced
Dedicated Channel (E-DCH)—constitutes a set of improvements that optimizes uplink
performance. Networks and devices supporting HSUPA became available in 2007. These
improvements include higher throughputs, reduced latency, and increased spectral
efficiency. HSUPA is standardized in Release 6. It results in an approximately 85 percent
increase in overall cell throughput on the uplink and more than 50 percent gain in user
throughput. HSUPA also reduces packet delays, a significant benefit resulting in
significantly improved application performance on HSPA network
Although the primary downlink traffic channel supporting HSDPA serves is a
shared channel designed for the support of services delivered through the packet-switched
domain, the primary uplink traffic channel defined for HSUPA is a dedicated channel that
could be used for services delivered through either the circuit-switched or the packet
switched domains. Nevertheless, by extension and for simplicity, the WCDMA-enhanced
uplink capabilities are often identified in the literature as HSUPA.
Such an improved uplink benefits users in a number of ways. For instance, some
user applications transmit large amounts of data from the mobile station such as sending
video clips or large presentation files. For future applications like VoIP, improvements will
balance the capacity of the uplink with the capacity of the downlink.
HSUPA achieves its performance gains through the following approaches:
#An enhanced dedicated physical channel.
#A short TTI, as low as 2 msec, which allows faster responses to changing radio conditions
and error conditions.
#Fast Node B-based scheduling, which allows the base station to efficiently allocate radio
resources.
#Fast Hybrid ARQ, which improves the efficiency of error processing. The combination
of TTI, fast scheduling, and Fast Hybrid ARQ also serves to reduce latency, which can
benefit many applications as much as improved throughput.

HSUPA can operate with or without HSDPA in the downlink, though it is likely
that most networks will use the two approaches together. The improved uplink mechanisms
also translate to better coverage and, for rural deployments, larger cell sizes.
HSUPA can achieve different throughput rates based on various parameters
including the number of codes used, the spreading factor of the codes, the TTI value, and
the transport block size in bytes, as illustrated in Table .
Table 3: HSUPA Peak Throughput Rates
Initial devices are Category 5 enabling peak user rates of close to 2 Mbps as
measured in actual network deployments. Category 6 devices will ultimately allow speeds
close to 5 Mbps, although only with the addition of interference cancellation methods that
boost SNR.
Beyond throughput enhancements, HSUPA also significantly reduces latency. In
optimized networks, latency will fall below 50 msec, relative to current HSDPA networks
at 70 msec. And with a later introduction of a 2 msec TTI, latency will be as low as 30
msec.

Mechanism
Due to the non-orthogonal uplink transmission in W-CDMA the principles applied
for the newly defined transport channel Enhanced Dedicated Channel (E-DCH) are
fundamentally different from HSDPA.
The shared resource in the system is the received interference at the Node B and a
transmission at a single UE can impact the raise over thermal noise as received by different
Node B. Continuous uplink power control is still an essential means of link adaptation due
to the well-known near-far problem. Consequently it was decided to support soft handover
for E-DCH to minimize intercell interference. Unlike HSDPA the scheduler is not aware
of the transmission buffer status, channel state and the UE transmission capabilities. Partly
this information will be signaled to the Node B via control signaling.
For the support of the new functionality several new physical channels were introduced.
 E-DPDCH: E-DCH Dedicated Physical Data Channel for dedicated uplink data
transmission. During data transmission, so-called Scheduling Information such as
buffer status, data priority and power headroom can be piggybacked.
 E-DPCCH: E-DCH Dedicated Physical Control Channel with the associated
control data for E-DPDCH detection and decoding. For the support of the scheduler
there is a Happy Bit that informs if the UE has sufficient resources for transmission.
 E-HICH: E-DCH HARQ Acknowledgement Indicator Channel to transmit HARQ
feedback information (ACK/NACK).
 E-RGCH: E-DCH Relative Grant Channel to grant dedicated resources (up, down,
hold) to a UE
 E-AGCH: E-DCH Absolute Grant Channel is a shared channel that allocates an
absolute resource for one or several UE.

In Figure the E-DCH data and signaling flow is illustrated. Based on the rate request
(Scheduling Information or Happy Bit) the Node B may respond with a resource allocation
via the absolute or a relative grant. The UE will use the grant for data transmission and the
Node B will acknowledge the received packets.
Figure 3.1 Data and Signal Flow
The HARQ protocol defined for HSDPA and for E-DCH is based on an n-channel
stop-and-wait protocol. Since out of sequence delivery is a regular event for this protocol,
there is a reordering function in place to provide in-sequence delivery to higher layer
protocols. Unlike in HSDPA this function is contained in a separate sub-layer called MAC-
es. MAC-esis located in the RNC since E-DCH supports soft handover and the packets can
be received by different Node Bs. It must also be noted that the ACK/NACK reception is
not reliable and there may be unwanted repetitions or even packet losses caused by
ACK/NACK misinterpretations at the sender. In that case RLC can recover the packets if
configured
in acknowledged mode (AM).

4.EVOLVED HSPA
4.1 Evolved HSPA:
HSPA+, or Evolved High-Speed Packet Access, is a technical standard for wireless,
broadband telecommunication. HSPA+ enhances the widely used WCDMA (UMTS)
based 3G networks with higher speeds for the end user that are comparable to the newer
LTE networks. HSPA+ was first defined in the technical standard 3GPP release 7 and
expanded further in later releases.
HSPA+ provides an evolution of High Speed Packet Access and provides data rates
up to 168 Megabits per second (Mbit/s) to the mobile device (downlink) and 22 Mbit/s
from the mobile device (uplink). Technically these are achieved through the use of a
multiple-antenna technique known as MIMO (for “multiple-input and multiple-output”)
and higher order modulation (64QAM) or combining multiple cells into one with a
technique known as Dual-Cell HSDPA.
The 168 Mbit/s and 22 Mbit/s represent theoretical peak speeds. The actual speed
for a user will be lower. In general, HSPA+ offer higher bitrates only in very good radio
conditions (very close to cell tower) or if the terminal and network both support either
MIMO or Dual-Cell HSDPA, which effectively use two parallel transmit channels with
different technical implementations.
The higher 168Mbps speeds are achieved by using multiple carriers with Dual-Cell
HSDPA and MIMO together simultaneously. The technology also delivers significant
battery life improvements and dramatically quicker wake-from-idle time – delivering a true
always-on connection. HSPA+ should not be confused with LTE, which uses a new air
interface based on OFDMA technology. HSPA+ is an evolution of HSPA that upgrades
the existing 3G network and provides a method for telecom operators to migrate towards
4G speeds without deploying a new radio interface

Wireless and networking technologists have defined a series of enhancements for
HSPA, some of which are specified in Release 7 and some of which are being finalized in
Release 8.
These include advanced receivers, MIMO, Continuous Packet Connectivity,
Higher-Order Modulation and One Tunnel Architecture.

5.ADVANTAGES
 Downloading speed-14Mbps Uploading speed-5.8Mbps
 Smooth for Transferring Large file, live streaming and web Browsing
 Low Latency below 50m sec
 It uses shared channel Transmissions
 Recovering Losing Data by Soft Combining Method At the time of
retransmission.

6.DISADVANTAGES
 Communication range
 If UE is far away from Base station (Node B) it cannot get the total Bandwidth
 Number of Users
 The Quality of service is Depends upon the Users
 Cost
 Expense to upgrade the whole system
 Expense to upgrade User Equipment.

7.APPLICATIONS
 Extension of DSCH
 Adaptive modulation and coding
o QPSK and 16-QPSk
o Multi coding transmission
o Fast channel condition
 Improved transmission efficiency
o Fat retransmission and physical layer HARQ
 Fast resource management
o Node B scheduling
 Reduced transmission latency
o 2ms TTI.

8.FUTURESCOPE
 Evolved of (HSPA+)
 Multiple Input Multiple Output Technology
 Higher Order Modulations
 Multi carrier Technology.

8.CONCLUSION
HSPA Evolution (3GPP Releases 7 and 8) enables operators to prolong the life of past
investments by further improving the performance of WCDMA systems. In particular,
HSPA Evolution introduces several new features that support higher data bit rates, reduce
latency, increase capacity, and improve support for VoIP and multicast services. Higher-
order modulation. In the downlink, the introduction of 64QAM increases the peak data bit
rate to as much as 21Mbps. Likewise, the introduction of 16QAM in the uplink increases
the peak data bit rate to 11Mbps.
Multiple input, multiple output (MIMO). In Release 7, MIMO is defined for
transmitting up to two streams. In this case, each stream can use QPSK or 16QAM,
extending the peak data bit rate of HSDPA to approximately 28Mbps. In Release 8, each
stream can use 64QAM, which extends the peak data bit rate to 42Mbps.Continuous packet
connectivity (CPC). Simulations show that the CPC concept in Release 7 boosts capacity
for VoIP by around 40% in the uplink and 10% in the downlink.
Layer-2 enhancements. Release 7 introduces a new MAC protocol, MAC-ehs,
which supports flexible RLC PDU sizes and the segmentation of RLC PDUs. In addition,
the MAC multiplexing capabilities have been improved so that RLC PDUs which carry
signaling or data from different radio access bearers can now be multiplexed into a single
MAC-ehs PDU. In Release 8, the enhancements made to the downlink protocol will be
applied to the uplink protocol.
Support for flexible RLC PDU sizes improves uplink coverage and helps reduce
processing and level-2 overhead. Enhanced CELL_FACH. In Release 7, HSDPA has been
activated for users in CELL_FACH. In Release 8, the uplink is improved by activating E-
DCH in CELL_FACH. This enhancement significantly improves user perception of
performance compared with Release 6, which must suspend data transmission for channel
switching. Multicast/broadcast single-frequency network (MBSFN). MBSFN calls for
simultaneous transmission of the exact same waveform from multiple cells. This way, the
UE receiver perceives the multiple MBSFN cells as one large cell.

Downlink-optimized broadcast (DOB). 3GPP proposes to take MBSFN operation
one step further, by introducing DOB as a special mode of 3.84Mbps timedivisionduplex
(TDD) operation in unpaired bands of spectrum.

REFERENCES
1) Holma, H., Toskala, A. WCDMA for UMTS. Radio access for third generation mobile
communications. West Sussex: John Wiley & Sons, 2004.
2) JuhaKarhonen, Introduction to 3G Mobile Communications, Artech House, 2003
3) http://www.3gamericas.org/index.cfm?fuseaction=page&sectionid=247
4) EDGE, HSPA, LTE: Broadband Innovation, September 2008, 3G Americas, RYSAVY
Research
5) David Maidment, Understanding HSDPA's Implementation Challenges, picoChip
Designs, 2005 http://www.eetimes.com/design/embedded-internet-
design/4009356/Understanding- HSDPA-s-Implementation-Challenges
6) Eiko Seidel, Standartization updates on HSPA Evolution, Nomor Research GmbH,
Munich, Germany, 2009
7) abcGSMA on HSPA
8)Nomor Research White Paper: Dual-Cell HSDPA and its Evolution
9) [R1-081546, “Initial multi-carrier HSPA performance evaluation”, Ericsson, 3GPP
TSG-RAN WG1 #52bis, April, 2008.]
10) 3GPP TR 25.825 (V1.0.0) “Dual Cell HSDPA Operation”
11) Nomor 3GPP Newsletter 2009-03: Standardization updates on HSPA Evolution
12) 3GPP TS 25.306 v11.0.0 http://www.3gpp.org/ftp/Specs/html-info/25306.htm
13) 3G Americas: “Global UMTS and HSPA Operator Status”, July 11, 2008.
14) Arthur D Little: “HSPA and Mobile WiMAX for Mobile Broadband Wireless Access
– An Independent Report Prepared for the GSM Association, March 27, 2007.

15) AT&T: Tom Keathley, “HSPA: Keys to a Successful Broadband Access Strategy”,
2008.16) Ericsson white paper: “Basic Concepts of HSPA”, February 2007.
16) Ericsson: “Cellular Evolution,” May 2006, submission to 3G Americas.
17) Ericsson: “HSPA and WiMAX Performance,” July 2007, submission to 3G Americas.
18) Ericsson: “HSPA Spectrum Efficiency Evolution”, June 2008, submission to 3G
Americas.
19) Ericsson: Johan Bergman et al, “HSPA Evolution – Boosting the performance of
mobile broadband access”, Ericsson Review No. 1, 2008.
20) Ericsson white paper: “HSPA, the Undisputed Choice for Mobile Broadband,” May
2007.
21) Ericsson white paper: “HSDPA Performance and Evolution”, No 3, 2006.

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