Patent ID: 8005449

Claim:
A received signal strength indicator (RSSI) circuit comprising: a subsampling circuit that processes an input signal comprising a sampling frequency, fs, wherein said subsampling circuit subsamples said input signal, wherein said input signal is subsampled to concentrate a power in a narrow bandwidth, and wherein said subsampling circuit comprises: a first switch and a first capacitor, wherein said first switch and said first capacitor are driven by an in-phase (I) sampling waveform; and a second switch and a second capacitor, wherein said second switch and said second capacitor are driven by a quadrature (Q) sampling waveform; an analog-to-digital converter (ADC) operatively connected to said subsampling circuit, wherein said ADC digitizes the subsampled signal; and a baseband detector operatively connected to said ADC, wherein said baseband detector detects a power from the digitized subsampled signal and creates an output signal.