Apparatus And Method Of RF Built In Self-Test (RFBIST) In A Radar System

A method of detecting a faulty receiver in a radar system having a plurality of transmitters and a plurality of receivers, the method comprising:

• transmitting a first signal from a first transmitter;
• receiving said first signal at a first receiver and a second receiver;
• transmitting a second signal from a second transmitter;
• receiving said second signal at said first receiver and said second receiver;
• and
• declaring a faulty first receiver if a correlation of said first signals received at said first receiver and said second receiver does not exceed a first threshold, and if a correlation of said first signal and said second signal received at said second receiver does not exceed a second threshold.

A radio frequency built in self-test (RF BIST) circuit, comprising:

• a plurality of transmitter circuits, including at least a first transmitter circuit operative to transmit a first radar signal and a second transmitter circuit operative to transmit a second radar signal;
• a plurality of receiver circuits, including at least a first receiver circuit and a second receiver circuit, each receiver circuit operative to receive a reflected radar signal including said first radar signal and said second radar signal;
• a test circuit operatively coupled to said plurality of receiver circuits and adapted to analyze received radar signals;
• said test circuit operative to declare a faulty first transmitter circuit if either of said first receiver circuit or said second receiver circuit do not detect a valid received first radar signal, and if both of said first receiver circuit and said second receiver circuit detect a valid received second radar signal;
• and
• said test circuit operative to declare a faulty first receiver circuit if a correlation of said first radar signals received at said first receiver circuit and said second receiver circuit does not exceed a first threshold, and if a correlation of said first radar signal and said second radar signal received at said second receiver circuit does not exceed a second threshold.

An automotive radar sensor, comprising:

• a plurality of transmitter circuits coupled to respective transmitting antennas, including at least a first transmitter circuit operative to transmit a first radar signal and a second transmitter circuit operative to transmit a second radar signal, each transmitter circuit operative to generate and couple transmitting signals to said transmitting antennas;
• a plurality of receiver circuits coupled to respective receiving antennas, including at least a first receiver circuit and a second receiver circuit, each receiver circuit operative to receive a reflected radar return signal including said first radar signal and said second radar signal;
• a digital radar processor (DRP) operative to control said plurality of transmitter circuits and said plurality of receiver circuits and to generate a radar image from received radar return signals, said DRP including an RF built in self-test (RFBIST) circuit operative to analyze the reflected radar return signals for transmitter circuit and/or receiver circuit faults;
• said RFBIST circuit operative to declare a faulty first transmitter circuit if either of said first receiver circuit or said second receiver circuit do not detect a valid received first radar signal, and if both of said first receiver circuit and said second receiver circuit detect a valid received second radar signal;
• and
• said RFBIST circuit operative to declare a faulty first receiver circuit if a correlation of said first radar signals received at said first receiver circuit and said second receiver circuit does not exceed a first threshold, and if a correlation of said first radar signal and said second radar signal received at said second receiver circuit does not exceed a second threshold.