Low Phase Noise Gunn Diode MIC VCOs for Application in Digital Radios

Performance data for Gunn diode microwave integrated circuit (MIC) voltage controlled oscillators (VCOs) for use in digital radios is presented. The measured phase noise of an 18.6 GHz VCO was -96 dBc/Hz at 100 KHz offset, which is significantly better than current published data for MESFET, HBT, and PHEMT VCOs at similar frequencies. These VCOs have application in systems such as 28 GHz LMDS receivers and digital radios (i.e. LAN) in the 18 to 38 GHz range, where low phase noise reduces both adjacent channel power (ACP) and bit error rate (BER).