Phase Tracking System for Ultra Narrow Bandwidth Applications

Recent advances make it possible to mitigate a number of drawbacks of conventional phase locked loops. These advances permit the design of phase tracking system with much improved characteristics that are sought after in modern communication system applications. A new phase tracking system is outlined which reduces the effects of VCO phase noise to an insignificant level. This fact permits extremely narrow bandwidth phase tracking systems to be realized, even when a VCO with poor phase noise characteristics is employed. The improvement in performance over conventional phase locked loops is analyzed, The new phase tracking system also has other benefits such as centre frequency and elimination of peaking in the transfer function, To implement the phase tracking system requires a frequency measurement. We outline a new highly integrated frequency measurement method suitable for narrow bandwidth applications. Experimental results from a prototype confirms theoretical results.