Method and apparatus for signal scanning for multimode receiver

A system comprising:

• a receiver including a mixer, an amplifier, a variable bandwidth filter, and a waveform synthesizer configured to synthesize a waveform at a variable frequency and provide the waveform to the mixer, wherein the receiver is configured to receive an input signal at an input, wherein the mixer, the amplifier, and the filter are disposed along a serial processing path and are configured to provide a processed signal corresponding to said input signal;
• a power spectral density computation module configured to generate a power spectral density of said processed signal over a selected frequency band, to provide a frequency domain signal for said frequency band, wherein the selected frequency band is variable;
• and
• a state machine configured to reconstruct, based on plural frequency domain signals provided by said power spectral density computation module for respective bands in a plurality of frequency bands, a frequency domain representation of said processed signal over a reconstruction band having a bandwidth larger than the predetermined wideband setting, and further configured to identify, based on said frequency domain representation, a spectral component corresponding to at least one cellular telephony access mode.

A system comprising:

• a first receiver module and a second receiver module in a multiple input multiple output (MIMO) communications system, the first and second receiver modules configured to process a first input signal and a second input signal, respectively, each receiver module including a mixer, an amplifier, and a variable bandwidth filter disposed along a serial processing path, the first and second receiver modules configured to provide a first processed signal corresponding to said first input signal and a second processed signal corresponding to said second input signal, respectively;
• a power spectral density computation module configured to generate a power spectral density of said first processed signal over a selected frequency band, to provide a frequency domain signal for said frequency band, wherein the selected frequency band is variable;
• a received signal strength indication (RSSI) module configured to measure voltage or power of said second processed signal;
• and
• a state machine having a first input coupled to an output of said power spectral density computation module and a second input coupled to an output of said RSSI module, said state machine configured to reconstruct, based on plural frequency domain signals provided by said power spectral density computation module for respective bands in a plurality of frequency bands, a frequency domain representation of said first processed signal over a reconstruction band having a bandwidth larger than the predetermined wideband setting, and further configured to identify, based on said frequency domain representation, a spectral component corresponding to at least one cellular telephony access mode.