Low Cost PLDROs for LMDS/MVDS Applications for 40 GHz Band

In HFC systems the infrastructure cost is dominated by the final distribution, the so-called "last mile". Market studies demonstrate that MVDS (Multipoint Video Distribution System) becomes even more attractive than HFC. For transmitting 16-QAM or 64-QAM in MVDS systems, a very good phase noise for local oscillators is required. In turn, this requires a high performance and low-cost (in particular for user units) PLO (Phase-Lock Oscillator) designs. This paper presents a low cost phase locked dielectric resonator oscillator (PLDRO) at 39 GHz for customer premises oscillator (CPED). The PLDRO is locked using a harmonic mixer as phase detector (down-converter in digital PLDRO). A comparison of analogue and digital approaches in terms of performance and flexibility is also presented. The PLDRO is used as part of an integrated MMIC receiver also presented in this paper.