Direct-sampled wide-band compressive receiver

A computer program product including one or more non-transitory machine-readable mediums encoded with instructions that when executed by one or more processors cause a process to be carried out for determining a frequency of a radio frequency (RF) signal, the process comprising:

• receiving a set of N digital signals, N being an integer number, wherein each digital signal represents a respective frequency sub-band of a frequency bandwidth covered by the set of N digital signals in combination;
• applying a common phase offset to the set of N digital signals to produce N reference signals;
• individually applying a different phase shift to each individual digital signal in the set of N digital signals to produce N phase-encoded signals, wherein individual phase-encoded signals are separated in phase from one another by a step value;
• summing the N reference signals to produce a summed reference signal;
• summing the N phase-encoded signals to produce a summed phase-encoded signal;
• dividing the summed reference signal and the summed phase-encoded signal into a plurality of frequency bins;
• detecting, in a particular frequency bin from among the plurality of frequency bins, a pulse representing the RF signal;
• performing delta phase measurements between the summed reference signal and the summed phase-encoded signal in the particular frequency bin;
• and
• based on the delta phase measurements, determining the frequency of the RF signal.

A radio frequency (RF) receiver system comprising:

• a plurality of digital phase shifters configured to produce a plurality of reference signals and a plurality of phase-encoded signals, wherein each digital phase shifter is configured to receive a respective digital input signal, to apply a phase offset to the respective digital input signal to produce a respective reference signal, and to apply a unique phase shift to the respective digital input signal to produce a respective phase-encoded signal;
• wherein the phase offset is common to all respective reference signals, and wherein the unique phase shift applied by each digital phase shifter to the respective phase-encoded signals is selected according to a phase encoding scheme;
• a first summer configured to combine the plurality of reference signals to produce a summed reference signal;
• a second summer configured to combine the plurality of phase-encoded signals to produce a summed phase-encoded signal;
• a channelizer sub-system configured to divide the summed reference signal and the summed phase-encoded signal into a plurality of frequency bins;
• and
• a detector configured to detect, in a particular frequency bin from among the plurality of frequency bins, a pulse representing an RF signal represented in one of the digital input signals and to perform delta phase measurements between the summed reference signal and the summed phase-encoded signal in the particular frequency bin to estimate a frequency of the RF signal.