Radar device

Patent metadata

Field	Value
Publication number	US-9239378-B2
Application number	US-201113824585-A
Country	US
Kind code	B2
Filing date	Sep 29, 2011
Priority date	Oct 7, 2010
Publication date	Jan 19, 2016
Grant date	Jan 19, 2016

Abstract

A radar device is provided, which includes a first sector radar and a second sector radar, each including a code generator that generates two code sequences, a multiplier that multiplies the two code sequences by a coefficient sequence, wherein the two coefficient sequences of the first and second sector radars, respectively, are orthogonal to each other, a transmission signal generator that modulates the orthogonalized two code sequences, and an RF transmitter that transmits the modulated signal including the two orthogonalized two code sequences. At least one of the two orthogonal coefficient sequences for the first and second sector radars, respectively, includes one or more negative coefficients. The two orthogonal coefficient sequences include coefficients, which are identical to each other, in a first transmission cycle, and include coefficients, which are different from each other, in a second transmission cycle different from the first transmission cycle.

First claim

The invention claimed is:

1. A radar device comprising:
a first code generator which, in operation, generates a first code sequence having a defined code length and a second code sequence having the defined code length;
a first multiplier which, in operation, multiplies the first code sequence for transmission in a first transmission cycle and the second code sequence for transmission in a second transmission cycle, respectively, by a first orthogonal coefficient sequence,
a first transmission signal generator which, in operation, generates a first transmission signal by modulating the first code sequence multiplied by the first orthogonal coefficient sequence and generates a second transmission signal by modulating the second code sequence multiplied by the first orthogonal coefficient sequence;
a first RF transmitter which, in operation, converts the first transmission signal into a first radio frequency transmission signal and transmits the first radio frequency transmission signal through a first transmission antenna in the first transmission cycle, and converts the second transmission signal into a second radio frequency transmission signal and transmits the second radio frequency transmission signal through the first transmission antenna in the second transmission cycle;
a second multiplier which, in operation, multiplies the second code sequence for transmission in the first transmission cycle and the first code sequence for transmission in the second transmission cycle, respectively, by a second orthogonal coefficient sequence, which is orthogonal to the first orthogonal coefficient sequence;
a second transmission signal generator which, in operation, generates a third transmission signal by modulating the second code sequence multiplied by the second orthogonal coefficient sequence and generates a fourth transmission signal by modulating the first code sequence multiplied by the second orthogonal coefficient sequence; and
a second RF transmitter which, in operation, converts the third transmission signal into a third radio frequency transmission signal and transmits the third radio frequency transmission signal through a second transmission antenna in the first transmission cycle, and converts the fourth transmission signal into a fourth radio frequency transmission signal and transmits the fourth radio frequency transmission signal through the second transmission antenna in the second transmission cycle,
wherein at least one of the first and second orthogonal coefficient sequences includes one or more negative coefficients, and the first and second orthogonal coefficient sequences respectively include coefficients, which are identical to each other, in one of the first and second transmission cycles, and include coefficients, which are different from each other, in the other of the first and second transmission cycles.

2. The radar device according to claim 1 , wherein the first code sequence and the second code sequence are code sequences which form a pair of complementary codes.

3. The radar device according to claim 1 ,
wherein the first multiplier further multiplies the first code sequence for transmission in a third transmission cycle and the second code sequence for transmission in a fourth transmission cycle, respectively, by a third orthogonal coefficient sequence;
wherein the first transmission signal generator further generates a fifth transmission signal by modulating the first code sequence multiplied by the third orthogonal coefficient sequence and generates a sixth transmission signal by modulating the second code sequence multiplied by the third orthogonal coefficient sequence;
wherein the first RF transmitter further converts the fifth transmission signal into a fifth radio frequency transmission signal and transmits the fifth radio frequency transmission signal through the first transmission antenna in a third transmission cycle, and converts the sixth transmission signal into a sixth radio frequency transmission signal and transmits the sixth radio frequency transmission signal through the first transmission antenna in a fourth transmission cycle;
wherein the second multiplier further multiplies the second code sequence for transmission in the third transmission cycle and the first code sequence for transmission in the fourth transmission cycle, respectively, by a fourth orthogonal coefficient sequence, which is orthogonal to the third orthogonal coefficient sequence;
wherein the second transmission signal generator further generates a seventh transmission signal by modulating the second code sequence multiplied by the fourth orthogonal coefficient sequence and generates an eighth transmission signal by modulating the first code sequence multiplied by the fourth orthogonal coefficient sequence;
wherein the second RF transmitter further converts the seventh transmission signal into a seventh radio frequency transmission signal and transmits the seventh radio frequency transmission signal through the second transmission antenna in the third transmission cycle, and converts the eighth transmission signal into an eighth radio frequency transmission signal and transmits the result eighth radio frequency transmission signal through the second transmission antenna in the fourth transmission cycle; and
wherein at least one of the third and fourth orthogonal coefficient sequences includes one or more negative coefficients, and the third and fourth orthogonal coefficient sequences respectively include coefficients, which are identical to each other, in one of the third and fourth transmission cycles, and include coefficients, which are different from each other, in the other of the third and fourth transmission cycles.

4. The radar device according to claim 1 , further comprising:
a first RF receiver which, in operation, converts a signal of a reflected wave obtained when the first and second radio frequency transmission signals transmitted from the first RF transmitter and the third and fourth radio frequency transmission signals transmitted from the second RF transmitter are reflected by a target into a baseband reception signal;
a first correlation value calculator which, in operation, calculates a first correlation value between the reception signal converted by the first RF receiver and a signal corresponding to one of the first and second transmission signals generated by the first transmission signal generator;
a first orthogonal code multiplier which, in operation, multiplies the first orthogonal coefficient sequence by the first correlation value;
a first addition processor which, in operation, adds the multiplication results of the first orthogonal code multiplier over the first and second transmission cycles;
a first sub separation code generator which, in operation, generates a first sub separation code capable of separating the first and second radio frequency transmission signals transmitted from the first transmission antenna by sub codes obtained by dividing the first and second code sequences by a predetermined number;
a second correlation value calculator which, in operation, performs calculation at each first half section and each second half section of each transmission cycle and multiplies a correlation value in the first half section and a correlation value in the second half section by the first sub separation code to calculate a second correlation value, according to the reception signal converted by the first RF receiver and the signal corresponding to one of the first and second transmission signals generated by the first transmission signal generator;
a second addition processor which, in operation, adds the calculation results of the second correlation value calculator over the first and second transmission cycles; and
a first match determiner which, in operation, outputs a first a

Assignees

• Kishigami Takaaki
• Nakagawa Yoichi
• Mukai Hirohito
• Panasonic Ip Man Co Ltd

Inventors

• Kishigami Takaaki
• Nakagawa Yoichi
• Mukai Hirohito

Classifications

• G01S13/222

  using random or pseudorandom pulse repetition frequency · CPC title

• G01S13/284 Primary

  using coded pulses · CPC title

• G01S7/023

  Interference mitigation, e.g. reducing or avoiding non-intentional interference with other HF-transmitters, base station transmitters for mobile communication or other radar systems, e.g. using electro-magnetic interference [EMI] reduction techniques (auxiliary means for detecting or identifying radar signals or the like G01S7/021; means for anti-jamming G01S7/36) · CPC title

• G01S13/91

  for traffic control (G01S13/93 takes precedence) · CPC title

• G01S13/288

  phase modulated · CPC title