Method and system for user speed estimation in wireless networks

Patent metadata

Field	Value
Publication number	US-9673922-B2
Application number	US-201414784685-A
Country	US
Kind code	B2
Filing date	Mar 14, 2014
Priority date	Apr 16, 2013
Publication date	Jun 6, 2017
Grant date	Jun 6, 2017

Abstract

A method for estimating the speed of a user equipment connected to a base station of a wireless network, the method comprising the following steps: —performing signal strength measurements (S) of a radio signal transmitted between the user equipment and the base station; —performing a spectral analysis ( 11 ) of the signal strength measurements; —determining the frequency of a local maximum in the power spectrum of the signal strength measurements; —estimating ( 12 ), from previously established reference data, the speed of the user equipment that corresponds to the determined frequency, the reference data associating a given user equipment speed with a certain determined frequency.

First claim

The invention claimed is:

1. A method for estimating the speed of a user equipment connected to a base station of a wireless network, the method comprising:
performing signal strength measurements of a radio signal transmitted between the user equipment and the base station;
performing a spectral analysis of the signal strength measurements;
determining the frequency of a local maximum in the power spectrum of the signal strength measurements;
estimating, from previously established reference data, the speed of the user equipment that corresponds to the determined frequency, the reference data associating a given user equipment speed with a certain determined frequency.

2. The method of claim 1 , wherein the local maximum in the power spectrum is the first local peak, in a frequency descending order, having an amplitude higher than a predefined threshold.

3. The method of claim 1 , wherein, if the estimated speed is below a predefined speed threshold, it further comprises:
denoising the signal strength measurements, so that removing noisy frequencies below a predefined frequency threshold;
performing a spectral analysis of the denoised signal strength measurements;
determining the frequency of a local maximum in the power spectrum of the denoised signal strength measurements;
estimating, from previously established reference data, the speed of the user equipment that corresponds to the determined frequency, the reference data associating a given user equipment speed with a certain determined frequency.

4. The method of claim 1 , wherein the reference data associates a given user equipment speed with a certain determined frequency for a given spatial decorrelation distance of the shadowing, the spatial decorrelation distance being relevant to the radio environment of the base station.

5. The method of claim 1 , wherein the estimated speed is the speed that is associated with the closest frequency, in the previously established reference data, to the determined frequency.

6. The method of claim 1 , wherein the signal strength measurements are performed by the user equipment on a downlink radio signal then reported to the base station.

7. The method of claim 1 , wherein the transmitted signal between the user equipment and the base station is a sounding reference signal.

8. The method of claim 1 , wherein the signal strength measurements are performed by the base station on an uplink signal transmitted from the user equipment.

9. A non-transitory computer readable medium having thereon a computer program including code sections for performing instructions corresponding to the method according to claim 1 when said computer program is implemented on a processing unit of a computer.

10. A processing unit for estimating the speed of a user equipment connected to a base station of a wireless network, the processing unit comprising:
means for performing a spectral analysis of signal strength measurements;
means for determining the frequency of a local maximum in the power spectrum of the signal strength measurements;
means for estimating, from previously established reference data, the speed of the user equipment that corresponds to the determined frequency, the reference data associating a given user equipment speed with a certain determined frequency.

11. The processing unit of claim 10 , further comprising means for denoising the signal strength measurements.

12. A base station comprising a processing unit according to claim 10 .

13. The base station of claim 12 , configured for performing signal strength measurements of a radio signal transmitted from a user equipment connected thereto.

Assignees

• Alcatel Lucent
• Inst Nat Rech Inf Automat

Inventors

• Haddad Majed
• Capdevielle Veronique
• Feki Afef
• Altman Eitan

Classifications

• G01S11/10

  using Doppler effect · CPC title

• H04W24/10

  Scheduling measurement reports {; Arrangements for measurement reports} · CPC title

• H04W4/027

  using movement velocity, acceleration information · CPC title

• H04W64/006 Primary

  with additional information processing, e.g. for direction or speed determination · CPC title

• H04B17/318 Primary

  Received signal strength · CPC title