www.gusucode.com > 基于simulink仿真载波和符号定时恢复源码程序 > 基于simulink仿真载波和符号定时恢复源码程序/code/readme.txt
readme.txt for synchronization examples. There are two models demonstrating both carrier and symbol timing recovery. The timing_recovery_1.mdl uses Simulinks variable step solver to create a continous time QPSK signal with both carrier and symbol rate errors. This is a relativly straight forward approach, but is computationally expensive. The sescond model, timing_recovery_2Q.mdl uses a purely discrete time approach using the same fractional sample delay approach as does the receiver. This can run much faster. The scope display blcoks are in an enabled subsystem, and turning these off provides another significant improvement in simulation speed. For the ultimate in speed, the transmit test signal could come from a file rather than being generated on the fly, but then the timing and carrier errors are fixed. Dick Benson 1/5/2010