Technique for detection of line-of-sight transmissions using millimeter wave communication devices

Patent metadata

Field	Value
Publication number	US-2016149302-A1
Application number	US-201514869891-A
Country	US
Kind code	A1
Filing date	Sep 29, 2015
Priority date	Nov 25, 2014
Publication date	May 26, 2016
Grant date	—

Abstract

Systems and methods for wireless communications are disclosed. More particularly, aspects of the present disclosure generally relate to techniques for wireless communications by a first apparatus comprising obtaining, via at least first and second receive antennas having different polarizations, first and second training signals transmitted from a second apparatus via at least first and second transmit antennas having different polarizations, determining, based on the first and second training signals, one or more characteristics for different transmit-receive antenna pairs, each pair comprising one of the first or second transmit antennas and one of the first or second receive antennas, and generating, based on one or more characteristics, a parameter indicative of whether a link path between the first and second apparatuses is line of sight (LOS).

First claim

What is claimed is:

1 . A first apparatus for wireless communications, comprising:
a first interface for obtaining, via at least first and second receive antennas having different polarizations, first and second training signals transmitted from a second apparatus via at least first and second transmit antennas having different polarizations; a processing system configured to:
determine, based on the first and second training signals, one or more characteristics for different transmit-receive antenna pairs, each pair comprising one of the first or second transmit antennas and one of the first or second receive antennas, and
generate, based on one or more characteristics, a parameter indicative of whether a link path between the first and second apparatuses is line of sight (LOS).

2 . The first apparatus of claim 1 , further comprising a second interface for outputting the parameter for transmission to the second apparatus.

3 . The first apparatus of claim 1 , wherein:
the first and second receive antennas comprise at least one vertically polarized receive antenna and at least one horizontally polarized receive antenna; and the first and second transmit antennas comprise at least one vertically polarized transmit antenna and at least one horizontally polarized transmit antenna.

4 . The first apparatus of claim 1 , wherein the one or more characteristics comprise receive power of training signals transmitted and received via a given one of the transmit-receive antenna pairs.

5 . The first apparatus of claim 1 , wherein the one or more characteristics comprise receive phase of training signals transmitted and received via a given one of the transmit-receive antenna pairs.

6 . The first apparatus of claim 1 , wherein the one or more characteristics comprise:
a first characteristic for a first transmit-receive antenna pair is determined based on the first training signal as received on the first receive antenna; and a second characteristic for a second transmit-receive antenna pair is determined based on the second training signal as received on the second receive antenna.

7 . The first apparatus of claim 6 , wherein the processing system is configured to indicate, via the parameter, that the link path between the first and second apparatuses is LOS if a difference or a ratio between the first and second characteristics is equal to or below a threshold value.

8 . The first apparatus of claim 7 , wherein the first and second characteristics and the threshold value are adjusted based on a factor.

9 . The first apparatus of claim 8 , wherein the factor is based on at least one of a cross-polarization number or polarization coefficients.

10 . The first apparatus of claim 8 , wherein the factor is based on at least an indication received from the second apparatus.

11 . The first apparatus of claim 6 , wherein the one or more characteristics further comprise:
a third characteristic for a third transmit-receive antenna pair is determined based on the first training signal as received on the second receive antenna; and a fourth characteristic for a fourth transmit-receive antenna pair is determined based on the second training signal as received on the first receive antenna.

12 . The first apparatus of claim 11 , wherein the parameter is generated based on at least one of:
the first and second characteristics; or the third and fourth characteristics.

13 . The first apparatus of claim 12 , wherein the processing system is configured to indicate, via the parameter, that the link path between the first and second apparatuses is LOS if a difference or a ratio between the first and second characteristics or a difference or a ratio between the third and fourth characteristics is equal to or below a threshold value.

14 . The first apparatus of claim 1 , wherein the first and second training signals are received as a part of a beamforming training procedure.

15 . The first apparatus of claim 1 , wherein:
the different polarizations of the first and second transmit antennas correspond to horizontal and vertical polarizations.

16 . The first apparatus of claim 1 , wherein:
the different polarizations of the first and second receive antennas correspond to horizontal and vertical polarizations.

17 . The first apparatus of claim 1 , wherein:
at least the first and second receive and transmit antennas comprise a dual polarized antenna.

18 . The first apparatus of claim 1 , wherein at least one of the first or second antenna is circularly polarized.

19 . A method for wireless communications by a first apparatus, comprising:
obtaining, via at least first and second receive antennas having different polarizations, first and second training signals transmitted from a second apparatus via at least first and second transmit antennas having different polarizations; determining, based on the first and second training signals, one or more characteristics for different transmit-receive antenna pairs, each pair comprising one of the first or second transmit antennas and one of the first or second receive antennas; and generating, based on one or more characteristics, a parameter indicative of whether a link path between the first and second apparatuses is line of sight (LOS).

20 . The method of claim 19 , further comprising outputting the parameter for transmission to the second apparatus.

21 . The method of claim 19 , wherein:
the first and second receive antennas comprise at least one vertically polarized receive antenna and at least one horizontally polarized receive antenna; and the first and second transmit antennas comprise at least one vertically polarized transmit antenna and at least one horizontally polarized transmit antenna.

22 . The method of claim 19 , wherein the one or more characteristics comprise receive power of training signals transmitted and received via a given one of the transmit-receive antenna pairs.

23 . The method of claim 19 , wherein the one or more characteristics comprise receive phase of training signals transmitted and received via a given one of the transmit-receive antenna pairs.

24 . The method of claim 19 , wherein the one or more characteristics comprise:
a first characteristic for a first transmit-receive antenna pair is determined based on the first training signal as received on the first receive antenna; and a second characteristic for a second transmit-receive antenna pair is determined based on the second training signal as received on the second receive antenna.

25 - 31 . (canceled)

32 . The method of claim 19 , wherein the first and second training signals are received as a part of a beamforming training procedure.

33 . The method of claim 19 , wherein:
the different polarizations of the first and second transmit antennas correspond to horizontal and vertical polarizations.

34 . The method of claim 19 , wherein:
the different polarizations of the first and second receive antennas correspond to horizontal and vertical polarizations.

35 - 36 . (canceled)

37 . A first apparatus for wireless communications, comprising:
means for obtaining, via at least first and second receive antennas having different polarizations, first and second training signals transmitted from a second apparatus via at least first and second

Assignees

• Qualcomm Inc

Inventors

• Sanderovich Amichai
• Diukman Iddo

Classifications

• H04B17/336 Primary

  Signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR] · CPC title

• H01Q3/24 Primary

  varying the orientation by switching energy from one active radiating element to another, e.g. for beam switching · CPC title

• H04B7/063

  Parameters other than those covered in groups H04B7/0623 - H04B7/0634, e.g. channel matrix rank or transmit mode selection · CPC title

• H04B7/0413 Primary

  MIMO systems · CPC title