Vehicle dynamics measuring apparatus and method using multiple GPS antennas

An apparatus for determining inertial velocity of a vehicle using GPS signals, said apparatus comprising:

• a first receiving antenna installed on a vehicle at a first known location for receiving GPS signals broadcast from multiple GPS transmitters;
• a second receiving antenna installed on the vehicle at a second known location for receiving the GPS signals, said second receiving antenna arranged on the vehicle at a predetermined distance from the first receiving antenna;
• and
• a controller for processing the GPS signals received from the first and second receiving antennas and monitoring a carrier frequency associated with the received GPS signals and determining a change in the carrier frequency of the GPS signals due to Doppler effect for each of the first and second receiving antennas, said controller determining a first inertial velocity vector for the first receiving antenna and a second inertial velocity vector for the second receiving antenna based on the change in carrier frequency, said controller further obtaining a vehicle heading and determining at least one of longitudinal and lateral velocity vectors of the vehicle as a function of the first and second inertial velocity vectors and the vehicle heading.

A method for determining the angular velocity of a vehicle using GPS signals, said method comprising the steps of:

• receiving GPS signals transmitted from multiple GPS transmitters via a first receiving antenna installed on a vehicle at a first known location;
• receiving the GPS signals transmitted from the multiple GPS transmitters via a second receiving antenna installed on the vehicle at a second known location, said second receiving antenna being arranged on the vehicle at a predetermined distance from the first receiving antenna;
• processing the GPS signals received by the first and second receiving antennas;
• monitoring a carrier frequency associated with each of the received GPS signals;
• determining a change in the carrier frequency due to Doppler effect for each of the first and second receiving antennas;
• determining an inertial velocity vector for each of the first and second receiving antennas based on the change in carrier frequency;
• and
• determining an angular rate of the vehicle based on the first and second inertial velocity vectors.

A method for determining inertial velocity of a vehicle using GPS signals, said method comprising the steps of:

• receiving GPS signals transmitted from multiple GPS transmitters via a first receiving antenna installed on a vehicle at a first known location;
• receiving the GPS signals transmitted from the multiple GPS transmitters via a second receiving antenna installed on the vehicle at a second known location, said second receiving antenna being arranged on the vehicle at a predetermined distance from the first receiving antenna;
• obtaining a vehicle heading;
• processing the GPS signals received by the first and second receiving antennas;
• monitoring a carrier frequency associated with each of the received GPS signals;
• determining a change in the carrier frequency due to Doppler effect for each of the first and second receiving antennas;
• determining a first inertial velocity vector for the first antenna and a second inertial velocity vector for the second antenna based on the change in carrier frequency for first and second receiving antennas, respectively;
• and
• determining at least one of longitudinal and lateral velocity vectors of the vehicle as a function of the first and second inertial velocity vectors and the vehicle heading.