The Softest Handoff Design Using Iterative Decoding (Turbo Coding) Byung K. Yi LGIC 3GPP2 TSG-C WG 3 Physical Layer Jan. 11, 2000

Presentation Outline Introduction and Motivation IS-95 Soft Handoff Scheme The Novel Forward Link System Model for the CCPC Handoff Scheme Simulation Results Over AWGN and Rayleigh Channels Upper Bounding Performances Over AWGN and Rayleigh Channels Reverse Link System Model for the CCPA Handoff Scheme Conclusions 2SH31599.ppt

Introduction and Motivation Recent Measurements of an operating IS-95 CDMA Cellular System indicate that About 30% to 50% of an average call period Is in soft-handoff process System Reliability during handoff becomes one of the major system performance parameters Turbo Codes have been adapted for the 3rd Generation Standards: CDMA 2000 (3GPP II) and 3GPP Are there techniques providing soft handoffs without increasing the transmitter power and bandwidth? Can we achieve a type of “Soft” Handoff for TDMA, FDMA, CDMA-to-CDMA System, or between various dual mode operations? 3SH31599.ppt

Introduction and Motivation (Cont’d) Are There Any Inherent benefits using the turbo code for next generation multi-media traffics beyond the Coding Gain? Answers Are “YES” Code Combining and Packet Combining (CCPC) Scheme in Conjunction With Iterative Turbo Decoding 4SH31599.ppt

IS-95 Soft Handoff System Model for the Cellular Handoff

IS-95 System Models for the Forward Link IS-95 CDMA Forward Link Receiver

IS-95 Soft Handoff Maximal Ratio Combiner of the Forward Link

IS-95 Soft Handoff System Model for the Reverse Link

The Novel Softest Handoff System Model for Forward Link Transmitter for the CCPC Handoff

The Novel Softest Handoff System Model for Forward Link Detailed Encoder for the CCPC Handoff for Code Rate 1/2 X1X1 + DDD + + I + DDD + + Y1Y1 X2X2 Y2Y2 Puncturer #1 Puncturer #2 MUX To Base Station A To Base Station B dkdk

The Novel Softest Handoff System Model for Forward Link Detailed Encoder for the CCPC Handoff for Code Rate 1/3 X1X1 + DDD I + DDD Y1Y1 Y2Y2 X2X2 Y3Y3 Y4Y4 Puncturer #1 Puncturer #2 MUX dkdk To Base Station A To Base Station B

The Novel Softest Handoff System Model for Forward Link Detailed Signal Puncturing for the CCPC Handoff

The Novel Softest Handoff System Model for Forward Link Mobile Receiver for the CCPC Handoff

The Novel Softest Handoff System Model for Forward Link Detailed Decoder for the CCPC Handoff Scheme

Simulation Results for the Code Rate 1/2 BER over AWGN Channel

Simulation Results for the Code Rate 1/2 FER over AWGN Channel

Simulation Results for the Code Rate 1/2 BER over Rayleigh Fading Channel

Simulation Results for the Code Rate 1/2 FER over Rayleigh Fading Channel

Upper bounding Performance BER over AWGN Upper bounding Performance for Code Rate 1/2

Upper bounding Performance FER over AWGN Upper bounding Performance for Code Rate 1/2

Upper bounding Performance FER over AWGN Channel for Different TX Power Cases Upper bounding Performance for Code Rate 1/2

Upper bounding Performance BER over AWGN Channel for Different TX Power Cases Upper bounding Performance for Code Rate 1/2

Upper bounding Performance FER over Rayleigh Fading Channel for the Same TX Power Case Upper bounding Performance for Code Rate 1/2

Upper bounding Performance BER over Rayleigh Fading Channel for the Same TX Power Case Upper bounding Performance for Code Rate 1/2

FER over Rayleigh Fading Channel for Different TX Power Cases Upper bounding Performance for Code Rate 1/2

BER over Rayleigh Fading Channel for Different TX Power Cases

Upper bounding Performance for Code Rate 1/2 FER Performance Comparison between 2-UNINTER and UNINT+INT Over AWGN Channel

Upper bounding Performance for Code Rate 1/2 BER Performance Comparison between 2-UNINTER and UNINT+INT Over AWGN Channel

Upper bounding Performance for Code Rate 1/2 BER Performance Comparison between 2-UNINTER and UNINT+INT Over Layleigh Fading Channel

Upper bounding Performance for Code Rate 1/3 FER over AWGN

Upper bounding Performance for Code Rate 1/3 BER over AWGN

Upper bounding Performance for Code Rate 1/3 BER over AWGN Channel for Different TX Power Cases

Upper bounding Performance for Code Rate 1/3 FER over AWGN Channel for Different TX Power Cases

Upper bounding Performance for Code Rate 1/3 BER over AWGN Channel for Different TX Power Cases

Upper bounding Performance for Code Rate 1/3 FER over Rayleigh Channel for Different TX Power Cases

Upper bounding Performance for Code Rate 1/3 BER over Rayleigh Channel for Different TX Power Cases

Conclusions We Proposed a New Soft Handoff Scheme Combining With CCPC Scheme With Iterative Turbo Decoding We Demonstrated Not Only an Unprecedented Coding Gain From Iterative Turbo Code, but Also More Than 3.2 dB and 4.0 dB Diversity Gains Due to the CCPC Scheme The CCPC Handoff Provides “the Softest” Handoff Mechanism for CDMA Systems The CCPC Handoff Can Allow a Type of Soft Handoff for TDMA, FDMA, CDMA-to- CDMA, or Between Dual Mode Operations The CCPC Handoff Scheme Provides Seamless and Transparent Handoff to Users 37SH31599.ppt