1. ECE 442 COMMUNICATION SYSTEM DESIGN LECTURE 6. SYNCHRONIZATION Husheng Li Dept. of EECS The University of Tennessee

2. SYNCHRONIZATION In CDMA systems, an alignment in the time is needed for both transmitter and receiver such that the PN sequence can be aligned. In TDMA systems, synchronization is also needed to avoid collisions. Two stages are needed for synchronization: Acquisition Tracking

3. ACQUISITION: DS-CDMA We can either use block acquisition or use sliding-correlator.

4. ACQUISITION: FREQUENCY HOPPING

5. TRACKING: DELAY-LOCKED LOOP The feedbacks of correlators force the local time to jump.

6. TAU-DITHER SYNCHRONIZATION The Tau-Dither loop has a simpler structure.

7. HOMEWORK Problem 15.1-1 Problem 15.1-2 Problem 15.1-3 Problem 15.4-1