发明名称 Multi-rate control loop for a digital phase locked loop
摘要 Methods and systems to generate control signals for timing recovery of a signal received over baseband communications systems are disclosed. The timing control circuit uses a multi-rate DSP structure for the implementation of the DSP functions in the control loop for use in an ASIC and requires a reduced DSP clock rate, which in turn reduces the need for pipelining and/or high-speed libraries. Thus lower latency, better tracking performance and lower power consumption are achieved. An example embodiment involves splitting the timing error signal, supplied at a given update rate, into a sum and a difference component, and processing each component in separate circuit chains at half the update rate. The resultant half-rate control signals from each separate circuit chain are joined to provide a control signal at the full update rate. Thus, implementations of the present disclosure perform like a full-rate structure, but require a halved DSP clock rate.
申请公布号 US8964925(B1) 申请公布日期 2015.02.24
申请号 US201313827587 申请日期 2013.03.14
申请人 PMC-Sierra US, Inc. 发明人 Saed Aryan
分类号 H04L7/00;H03L7/08 主分类号 H04L7/00
代理机构 代理人 Haszko Dennis R.
主权项 1. A method for generating a pair of loop filter outputs in a digital signal processing (DSP) timing recovery circuit, the method comprising: receiving, in one clock cycle, a pair of consecutive samples of an error signal from a timing error detector of the DSP timing recovery circuit; generating a integrator path signal by applying a single loop filter integration to a sum of the pair of consecutive samples of the error signal; generating a first loop filter output of the pair of loop filter outputs as a function of the integrator path signal and a first sample of the pair of consecutive samples of the error signal; and generating a second loop filter output of the pair of loop filter outputs as a function of the integrator path signal and a second sample of the pair of consecutive samples of the error signal.
地址 Sunnyvale CA US