Process for controlling the antennas of a hands-free system of an automotive vehicle and corresponding device
AssigneeSiemens VDO Automotive Corporation
InventorAlain Brillon
Life of this patent
Estimating the term…
Abstract
In this process for controlling at least two groups of antennas, a coded signal (26) is emitted by a first group of antennas, whilst the antennas of a second group emit a residual signal (28) similar to the coded signal but of lesser amplitude. The coding used in this case is such that the coded signal (26) has dead time. A parasitic signal (34) is sent to the second group of antennas (6) during dead time of the coded signal (26) sent to the first group of antennas.
Claims14
Process for controlling at least two groups of antennas (4, 6), comprising:
- sending a coded signal to a first group of antennas (4) and to a second group of antennas (6);
- emitting the coded signal (26) from the first group of antennas (4) whilst a second group of antennas (6) emit a residual signal (28) similar to the coded signal but of lesser amplitude, the coding used being such that the coded signal has dead time;
- and
- sending a parasitic signal (34) to the second group of antennas (6) during the dead time of the coded signal,
- wherein the residual signal is based on the coded signal and the parasitic signal.
Control device, comprising:
- means (10) to send alternatively a coded signal to several groups of antennas, the coding used being such that the coded signal has dead time, wherein,
- said means sends a parasitic signal to a second group of antennas (6) when a coded signal is sent to a first group of antennas (4), the parasitic signal being sent to the antennas of the second group during the dead time of the coded signal.
A system for hands-free access to a vehicle, comprising:
- a first antenna (4);
- a second antenna (6);
- and
- a code transmitter configured to transmit radio frequency amplitude modulated coded signals of predetermined power to the first antenna and to the second antenna,
- the code transmitter comprising a multiplexer (10) connected to input a coded signal (18) and having a coded signal output (22) for sending the coded signals to the first and second antennas, wherein,
- a first coded signal is sent from the coded signal output to the first antenna, the first coded signal comprising dead time within amplitude modulated code signals, and
- a second coded signal is sent from the coded signal output to the second antenna, the second coded signal comprising a residual signal of the first coded signal superimposed, during the dead time, with a parasitic signal such that the second coded signal is a combination of the residual signal and the parasitic signal, the parasitic signal appearing during the dead time of the first coded signal.
Dependencies are inferred from the claim text.