Antenna system and method for mitigating multi-path effect

• US 8,515,378 B2
• Filed: 06/15/2010
• Issued: 08/20/2013
• Est. Priority Date: 06/15/2009
• Status: Expired due to Fees

• Current Assignee: AGC Automotive Americas R&D, Inc (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:
  US12/815,833
• Publication Number:
  US 20100317309A1
• Time in Patent Office: 1,162 Days
• Field of Search: 455130-355, 455/11.1, 455/562.1
• US Class Current: 455/296
• 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. A method of conditioning an RF signal received by a single antenna to mitigate a multi-path effect on the RF signal prior to providing a conditioned signal to a receiver, said method comprising the steps of:

splitting the RF signal received by the single antenna into a first non-phase shifted signal and a second non-phase shifted signal;

shifting the phase of the second non-phase shifted signal to produce a first phase shifted signal;

combining the first non-phase shifted signal and phase shifted signal to produce a first conditioned signal;

determining and recording a quality of the first conditioned signal;

shifting the phase of the second non-phase shifted signal to produce a second phase shifted signal different from the first phase shifted signal;

combining the first non-phase shifted signal and the second phase shifted signal to produce a second conditioned signal;

determining and recording a quality of the second conditioned signal;

comparing the quality of the first conditioned signal and the second conditioned signal to determine which of the conditioned signals has a highest quality; and

providing the conditioned signal determined to have the highest quality to the receiver.

2. A method as set forth in claim 1 further comprising the step of shifting the phase of the second non-phase shifted signal to produce a third phase shifted signal different from the first and second phase shifted signals.

3. A method as set forth in claim 2 further comprising the step of combining the first non-phase shifted signal and the third phase shifted signal to produce a third conditioned signal.

4. A method as set forth in claim 3 further comprising the step of determining and recording a quality of the third conditioned signal.

5. A method as set forth in claim 4 wherein said step of comparing the quality is further defined as comparing the quality of the first, second, and third non-phase shifted signals to determine which of the conditioned signals has a highest quality.

6. A method as set forth in claim 5 wherein said step of providing the conditioned signal is further defined as providing the conditioned signal determined to have the highest quality to the receiver.

7. A method as set forth in claim 6 wherein said step of providing the conditioned signal is further defined as shifting the phase of the second non-phase shifted signal to the phase shift associated with the conditioned signal having the highest quality.

8. A method as set forth in claim 1 wherein said step of providing the conditioned signal is further defined as shifting the phase of the second non-phase shifted signal to the phase shift associated with the conditioned signal having the highest quality.