LAUSR

This letter presents a wideband on-chip frequency detector implemented in a 65-nm CMOS technology. The frequency detector is composed of a fish bone like transmission line and a series of distributed power detectors with a parallel-to-serial readout circuit. A slow wave structure is employed in the transmission line for improved area efficiency. The frequency is extracted from the waveform profile of the standing wave formed along the transmission line, which is obtained by the local power levels of the wave measured by the detectors. The extracted frequencies showed a good agreement with the injected signal frequency for a measured frequency range of 120–360 GHz. The chip size is $400\times 180\,\,\mu \text{m}^{2}$ excluding probing pads.