Method and apparatus for radar waveforms using orthogonal sequence sets

Abstract

Systems, methods, and apparatus for radar waveforms using orthogonal sequence sets are disclosed. In one or more examples, a vehicle for autonomous driving comprises a radar sensor. In some examples, the radar sensor comprises a waveform transmission module adapted to generate a phase-coded waveform based on a set of concatenated orthogonal sequences. Also, in some examples, the radar sensor comprises a receiver adapted to estimate a range and Doppler from a received echo from the phase-coded waveform. In one or more examples, the orthogonal sequences are Zadoff-Chu (ZC) sequences.

1 . A method for suppressing interference in a radar system, comprising:
 assigning a first orthogonal sequence to the radar system;   transmitting a phase-coded waveform based on the first orthogonal sequence;   receiving an echo from transmission of the phase-coded waveform;   identifying correlation peaks in the echo; and   determining a Doppler estimate of delay between the correlation peaks.   
     
     
         2 . The method as in  claim 1 , further comprising determining a source of the echo. 
     
     
         3 . The method as in  claim 1 , further comprising modulating information onto the phase-coded waveform. 
     
     
         4 . The method as in  claim 1 , wherein the first orthogonal sequence is a set of concatenated orthogonal sequences. 
     
     
         5 . The method as in  claim 1 , wherein the radar system is part of a vehicle system. 
     
     
         6 . The method as in  claim 1 , wherein the orthogonal sequence is based on a cellular system and cellular sequences. 
     
     
         7 . The method as in  claim 6 , wherein the orthogonal sequence is a Zadoff-Chu sequence. 
     
     
         8 . The method as in  claim 1 , wherein the orthogonal sequence is designed to suppress bandlimited interference. 
     
     
         9 . The method as in  claim 8 , wherein the radar system is part of a vehicle system and further comprises detecting an echo of the vehicle. 
     
     
         10 . The method as in  claim 1  further comprising distinguishing echoes within a range ambiguity distance. 
     
     
         11 . A radar system, comprising:
 means for assigning a first orthogonal sequence to the radar system;   means for transmitting a phase-coded waveform based on the first orthogonal sequence;   means for receiving an echo from transmission of the phase-coded waveform;   means for identifying correlation peaks in the echo; and   means for determining a Doppler estimate of delay between the correlation peaks.   
     
     
         12 . The radar system as in  claim 11 , wherein the means for transmitting is a waveform transmission module adapted to generate a waveform configured as a radar signals. 
     
     
         13 . The radar system as in  claim 12 , wherein means for receiving an echo is a receiver module adapted to receive signals, including radar echoes, interferences, and ghost echoes and wherein the receiver module is adapted to distinguish between radar echoes, interferences and ghost echoes. 
     
     
         14 . The radar system as in  claim 11 , wherein the first orthogonal sequence is a complex mathematical sequence providing a signal of constant amplitude and wherein received signals at the means for receiving are uncorrelated with each other. 
     
     
         15 . The radar system as in  claim 11 , wherein the first orthogonal sequence is cyclically shifted version of an original code. 
     
     
         16 . The radar system as in  claim 11 , wherein the first orthogonal sequence suppresses interference. 
     
     
         17 . The radar system as in  claim 11 , wherein the employing pseudo-random number (PRN) codes to provide ranging capability by estimating the correlating the echo with a local sequence comprising peaks. 
     
     
         18 . A vehicular radar system, comprising:
 a processor adapted to select a Zadoff-Chu sequence;   a transmitter module for generating a concatenated waveforms including the transmitter identification information and vehicle identification information, wherein each portion of the waveform includes a spectrum spreading symbol;   a receiver module to receive radar signals and adapted to correlate a received signal with an original signal and to identify correlation peaks; and   integration means for vehicle-to-everything (V2X) infrastructure.   
     
     
         19 . The vehicular radar as in  claim 18  contained within a terrestrial vehicle. 
     
     
         20 . The vehicular radar as in  claim 18  contained within an aerial vehicle.