Methods, apparatuses, and devices for positioning mobile devices using measured receiver gain

Patent metadata

Field	Value
Publication number	US-9491583-B2
Application number	US-201414226739-A
Country	US
Kind code	B2
Filing date	Mar 26, 2014
Priority date	Mar 26, 2014
Publication date	Nov 8, 2016
Grant date	Nov 8, 2016

Abstract

Methods, apparatuses, and devices are disclosed that may be used to estimate a location of a mobile device using, for example, one more receiver gains that may bring about adjustment of received signal strength indications of a radio heatmap. Such adjustment may allow a mobile device to accurately estimate a present location of a mobile device using, for example, a radio heatmap.

First claim

What is claimed is:

1. A method comprising, at a mobile device:
receiving one or more messages from a wireless access point, said received one or more messages comprising an indication of a received first signal strength of one or more first signals transmitted by said mobile device and acquired at said wireless access point;
measuring a second signal strength, said second signal strength corresponding to strength of one or more second signals used to transmit at least one of said received one or more messages;
computing a receiver gain of said mobile device based, at least in part, on said second signal strength and said indication of said received first signal strength; and
applying said receiver gain to compute an estimated location of said mobile device.

2. The method of claim 1 , wherein said applying said receiver gain to compute said estimated location of said mobile device further comprises:
adjusting expected or predicted values of said received first signal strength using said computed receiver gain.

3. The method of claim 1 , wherein said computing said receiver gain is based, at least in part, on an indication of transmission power employed at said mobile device to transmit said one or more first signals.

4. The method of claim 1 , further comprising said mobile device computing said receiver gain based, at least in part, on an indication of transmission power used at said wireless access point to transmit one or more signals comprising at least one of said received one or more messages.

5. The method of claim 1 , wherein said computing said receiver gain is based, at least in part, on antenna gain of one or more antennas used by said wireless access point to transmit one or more signals comprising said received one or more messages.

6. The method of claim 1 , wherein said applying said receiver gain to compute said estimated location of said mobile device further comprises: computing said receiver gain substantially according to:
Rx Gain= RSSI@MD−AP Tx power−( RSSI@AP −Mobile Tx power+ AP gain), where:

RSSI@MD represents said measured second signal strength;
AP Tx power represents an indication of transmission power used at said wireless access point to transmit one or more signals comprising at least one of said received one or more messages;
RSSI@AP represents said indication of said received first signal strength of said one or more first signals transmitted by said mobile device;
Mobile Tx power represents an indication of transmission power employed at said mobile device to transmit said one or more first signals; and
APgain represents an antenna gain.

7. The method of claim 6 , wherein said RSSI@AP is derived, at least in part, from a link margin value indicated in a link measurement report frame.

8. The method of claim 1 , further comprising:
measuring a signal strength of one or more signals used to transmit one or more messages from said mobile device and received at said wireless access point.

9. A mobile device comprising:
a receiver configured to acquire one or more signals from a communications channel, said one or more signals used to transmit one or more messages from a communications network; and
one or more processors coupled to said receiver, configured to:
measure, at said mobile device, a signal strength of said one or more signals acquired from said communications channel;
compute a receiver gain of said mobile device based, at least in part, on said signal strength measured at said mobile device of one or more signals acquired from said communications channel and an indication of signal strength of one or more signals measured at a wireless access point, said indication of signal strength measured at said wireless access point being provided using said one or more messages; and
apply said receiver gain to compute an estimated location of said mobile device.

10. The mobile device of claim 9 , wherein said one or more processors are additionally configured to:
adjust expected or predicted values of received signal strength of one or more signals transmitted by said mobile device and received at said wireless access point using said computed receiver gain.

11. The mobile device of claim 9 , wherein said one or more processors are additionally configured to:
compute said receiver gain based, at least in part, on an indication of transmission power employed at said mobile device to transmit said one or more signals measured at said wireless access point.

12. The mobile device of claim 9 , wherein said one or more processors are additionally configured to:
compute said receiver gain based, at least in part, on an indication of transmission power used at said wireless access point to transmit one or more signals comprising at least one of said one or more messages.

13. The mobile device of claim 9 , wherein said one or more processors are additionally configured to:
compute said receiver gain based, at least in part, on antenna gain of one or more antennas used by said wireless access point to transmit said one or more signals for providing said one or more messages.

14. The mobile device of claim 9 , wherein said one or more processors are additionally configured to:
compute said receiver gain substantially according to:
Rx Gain= RSSI@MD−AP Tx power−( RSSI@AP− Mobile Tx power+ AP gain), where:

RSSI@MD represents said signal strength measured at said mobile device;
AP Tx power represents an indication of transmission power used at said wireless access point to transmit said one or more signals comprising at least one of said one or more messages;
RSSI@AP represents said indication of said signal strength measured at said wireless access point;
Mobile Tx power represents an indication of transmission power employed at said mobile device to transmit said one or more signals comprising said signal strength measured at said wireless access point; and
APgain represents an antenna gain.

15. The mobile device of claim 14 , wherein said one or more processors are additionally configured to:
compute said RSSI@AP, at least in part, from a link margin value indicated in a link measurement report frame.

16. An article comprising:
a non-transitory storage medium comprising machine-readable instructions stored thereon which are executable by one or more processors of a mobile device, comprising: code to obtain of one or more messages received from a communications channel;
code to measure a signal strength at said mobile device of one or more signals used to transmit at least one of said received one or more messages;
code to compute a receiver gain of said mobile device based, at least in part, on said signal strength measured at said mobile device and an indication of signal strength of one or more signals transmitted by said mobile device and measured at a wireless access point, said indication of said signal strength measured at said wireless access point being provided in at least one of said received one or more messages; and
code to apply said receiver gain to compute an estimated location of said mobile device.

17. The article of claim 16 , wherein said non-transitory storage medium further comprises:
code to adjust expected or predicted values of received signal strength using said computed receiver gain.

18. The article of claim 16 , wherein said non-transitory storage medium further comprises:
code to compute said receiver gain based, at least in part, on an indication of transmission power employed at said mobile device to transmit
said one or more signals trans

Assignees

• Qualcomm Inc

Inventors

• Venkatraman Sai Pradeep
• Zhang Gengsheng
• Aldana Carlos H
• Gao Weihua

Classifications

• G01S5/0244

  Accuracy or reliability of position solution or of measurements contributing thereto · CPC title

• G01S5/02521

  using a radio-map · CPC title

• G01S5/0205

  Details · CPC title

• H04W52/245

  taking into account received signal strength · CPC title

• H04W64/00 Primary

  Locating users or terminals {or network equipment} for network management purposes, e.g. mobility management · CPC title