Call Processing In CDMA
- 1. Presented By: Mukesh Kumar
- 2. Session objectives: Registration Call Procedure Mobile Terminated Call Mobile Originated Call
- 3. Registration Process by which an idle mobile lets the system know it’s awake . Registration allows mobile’s home switch to know mobile’s current location so that i/c calls can be delivered. Registration allows the system to page MS only in the area where the MS is currently located, to eliminate congestion on PCHs. Registration message(By probing ) Base station ack. order
- 4. Types Of Registration Power ON Power OFF Timer Based Distance based Zone based Ordered Parameter change Implicit Traffic channel When MS is turned ON Just when MS is turned OFF After a certain timer expires If MS moves to further cell If MS moves in/out of the zone BS requests the registration. If MS parameter changes BS infers the MS position. For registration in active mode
- 5. ) ) ) ) ) ) ) ) ) ) ) Registration message ( ( ( ( ( ( ( ( ( ( ( Registration accept order Location update request Location update accepted MSC BS MS LOCAL REGISTRATION
- 6. States of call Power-Up Mobile Station Initialization Mobile Station Idle State System Access State MS Control on Traffic Channel State Synch Channel MSG Received Pilot Channel Acquired MS Acquires System Timing Directed to Traffic Channel End Use of Traffic Channel Receives Page Originates, or Registers Unable to receive Paging Channel Message Receipt of Acknowledgement to other than Origination or Page Response message.
- 7. States Of Call Initialization State System determination sub state Pilot channel acquisition sub state Sync channel acquisition sub state Timing change sub state 2. Idle state Paging channel monitoring Idle handoff 3. Access state 4. Traffic channel state Update overhead information Page response Mobile station origination attempt Registration access Mobile station order/message response Mobile station message transmission Voice as well as signaling Voice frames vary depending on the vocoder rate Blank and burst is all signaling data only
- 8. MSC BSC BTS PAGING ACCESS PAGING TRAFFIC CHANNEL Receiving an incoming call Page message is sent on PCH MS responds on Access channel Channel assignments on paging Mobile gets a traffic channel
- 9. Mobile Terminated Call All idle MS monitor the PCH to receive i/c calls. When an incoming call appears, PCH notifies MS in general page message. MS sends a page response message on access channel. System sets up a TCH for the call, then notifies MS to use it with a Channel Assignment Message. MS and BS notice each other’s TCH signals and confirm their presence by exchanging acknowledgement messages.
- 10. BS and MS negotiate what type of call this will be –i.e., 13k voice etc. MS is told to ring and given a “ calling line ID” to display. When user presses send button, audio path is completed and call proceeds
- 11. Paging channel MS Access channel Forward Traffic channel Reverse Traffic channel Base station ack. order Channel assignment message General page message Continuous frames of all 000’s Base station ack. order Service connect message Page response message Traffic channel preamble: Frame of 000’s Mobile station ack. order Service connect complete message Mobile Terminated Call
- 12. MTC/MOC BTS MS paging request channel request immediate assignment paging response authentication request authentication response ciphering command ciphering complete setup call confirmed assignment command assignment complete alerting connect connect acknowledge data/speech exchange BTS MS channel request immediate assignment service request authentication request authentication response ciphering command ciphering complete setup call confirmed assignment command assignment complete alerting connect connect acknowledge data/speech exchange MTC MOC
- 13. Mobile Originated Call MS user dials desired digits and presses send key. MS transmits an origination message on access channel. System acknowledges on PCH. System arrange resources for call and transmitting on TCH. System notifies MS in channel assignment message on PCH.
- 14. MS arrives on TCH. MS and BS notice each other’s TCH signal and confirm their presence by exchanging acknowledgement messages. BS and MS negotiate what type of call this will be… i.e., 13k voice, etc. Audio circuit is completed and the mobile caller hears ringing.
- 15. Paging channel MS Access channel Forward Traffic channel Reverse Traffic channel Base station ack. order Channel assignment message Continuous frames of all 000’s Base station ack. order Service connect message Origination message(By probing) Traffic channel preamble: Frame of 000’s Mobile station ack. order Service connect message complete Mobile Originated Call
- 16. THANK YOU