Antenna system and method for mitigating multi-path effect

• US 9,094,115 B2
• Filed: 07/02/2013
• Issued: 07/28/2015
• Est. Priority Date: 06/15/2009
• Status: Expired due to Fees

• Current Assignee: AGC Automotive Americas Co. (AGC, Inc.)
• Original Assignee: AGC Automotive Americas R&D, Inc (AGC, Inc.)
• Inventors: Lee, Ming, Villarroel, Wladimiro, Horiki, Yasutaka, Lee, Kwan-ho
• Primary Examiner(s): Le, Lana N
• Application Number:
  US13/933,605
• Publication Number:
  US 20130295864A1
• Time in Patent Office: 756 Days
• US Class Current: 1/1
• CPC Class Codes: H01Q 1/1271 for mounting on windscreens
• CPC Class Codes: H01Q 1/325 characterised by the location of the antenna on the vehicle
• CPC Class Codes: H01Q 3/2605 Array of radiating elements provided with a feedback control over the element weights, e.g. adaptive arrays
• CPC Class Codes: H01Q 3/34 by electrical means active lenses or reflecting arrays H01Q3/46
• CPC Class Codes: H04B 17/345 Interference values signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR] H04B17/336
• CPC Class Codes: H04B 7/002 Reducing depolarization effects
• CPC Class Codes: H04B 7/0848 Joint weighting
• CPC Class Codes: H04B 7/0857 using maximum ratio combining techniques, e.g. signal-to- interference ratio [SIR], received signal strenght indication [RSS]
• CPC Class Codes: H04B 7/086 using weights depending on external parameters, e.g. direction of arrival [DOA], predetermined weights or beamforming
• CPC Class Codes: H04B 7/10 Polarisation diversity; Directional diversity

Abstract

An antenna system and method utilize a splitter electrically connectable to a single antenna for splitting an RF signal into two signals. A variable phase shifter shifts the phase of one of the signals. A combiner combines the phase shifted and non-phase shifted signals to produce a conditioned signal. A quality examiner circuit changes the amount of phase shift provided by the variable phase shifter to produce a plurality of different conditioned signals. The quality examiner circuit then determines a quality of each conditioned signal and changes the phase shift again to provide the highest quality conditioned signal to a receiver.

Claims

1. An antenna system for mitigating a multi-path effect on a radio frequency (RF) signal received by a single antenna and for providing a conditioned signal to a receiver, said system comprising:

a splitter electrically connectable to the single antenna wherein said splitter splits the RF signal received by the single antenna into a first non-phase shifted signal and a second non-phase shifted signal;

a variable phase shifter electrically connected to said splitter for receiving the second non-phase shifted signal, wherein said phase shifter phase shifts the second non-phase shifted signal to produce a first phase shifted signal and a second phase shifted signal that is different from the first phase shifted signal;

a combiner having inputs electrically connected to said splitter and said variable phase shifter, said combiner receives and combines the first non-phase shifted signal and the first phase shifted signal to produce a first conditioned signal, and said combiner receives and combines the first non-phase shifted signal and the second phase shifted signal to produce a second conditioned signal; and

a quality examiner circuit electrically connected to an output of said combiner to receive the first and second conditioned signals, with said quality examiner circuit configured to determine which of the conditioned signals has a highest quality, and wherein said quality examiner circuit provides the one of the first and second conditioned signals determined to have the highest quality to the receiver.

2. A system as set forth in claim 1 wherein said quality examiner circuit is further defined as a microprocessor.

3. A system as set forth in claim 1 wherein said variable phase shifter shifts the phase of the second non-phase shifted signal to a phase shift associated with the one of the first and second conditioned signals determined to have the highest quality.

4. A system as set forth in claim 1 wherein said variable phase shifter may phase shift the second non-phase shifted signal to produce a third phase shifted signal different from the first and second phase shifted signals.

5. A system as set forth in claim 4 wherein said combiner receives and combines the first non-phase shifted signal and the third phase shifted signal to produce a third conditioned signal.

6. A system as set forth in claim 5 wherein said quality examiner circuit determines and records a quality of the third conditioned signal.

7. A system as set forth in claim 6 wherein said quality examiner circuit compares the quality of the first, second, and third conditioned signals to determine which of the conditioned signals has a highest quality.

8. A system as set forth in claim 7 wherein said quality examiner circuit provides the one of the first, second, and third conditioned signals determined to have the highest quality to the receiver.

9. A system as set forth in claim 8 wherein said variable phase shifter shifts the phase of the second non-phase shifted signal to a phase shift associated with the one of the first, second, and third conditioned signals determined to have the highest quality.

10. A system as set forth in claim 1 further comprising an analog-to-digital converter (ADC) electrically connected to said combiner and said quality examiner circuit for receiving the conditioned signal from said combiner and providing a digital representation of the conditioned signal to said quality examiner circuit.

11. A system as set forth in claim 1 wherein signal quality is further defined as signal strength.

12. A system as set forth in claim 1 wherein said quality examiner circuit includes an input for receiving the conditioned signal and an output electrically connected to the receiver for providing the conditioned signal to the receiver.

13. A system as set forth in claim 1 wherein said output of said combiner is electrically connected to the receiver for providing the conditioned signal to the receiver.

14. A system as set forth in claim 1 wherein said quality examiner communicates the quality of at least one of the first and second conditioned signals to said variable phase shifter.

15. A system as set forth in claim 14 wherein said variable phase shifter changes the amount of phase shift of the second non-phase shifted signal based on the quality of at least one of the first and second conditioned signals.