Systems, apparatus, and methods for antenna selection

Patent metadata

Field	Value
Publication number	US-9287953-B2
Application number	US-201213711406-A
Country	US
Kind code	B2
Filing date	Dec 11, 2012
Priority date	May 21, 2012
Publication date	Mar 15, 2016
Grant date	Mar 15, 2016

Abstract

This disclosure provides systems, methods, and apparatus for mobile transmit diversity. In one aspect, a wireless communication apparatus is provided. The wireless communication apparatus includes a transmit circuit configured to transmit wireless communications via either a first antenna or a second antenna. The wireless communication apparatus further includes a receive circuit configured to receive wireless communications using either the first antenna or the second antenna. The wireless communication apparatus further includes a controller configured to switch the transmit circuit and the receive circuit from transmitting and receiving wireless communications via the first antenna to transmit and receive wireless communications via the second antenna in response to detecting that a first receive power level of the first antenna is less than a second receive power level of the second antenna and a difference between the second receive power level and the first receive power level is greater than a threshold.

First claim

What is claimed is:

1. A wireless communication apparatus, comprising:
a transmit circuit configured to transmit wireless communications via either a first antenna or a second antenna;
a receive circuit configured to receive wireless communications using either the first antenna or the second antenna; and
a controller configured to switch the transmit circuit and the receive circuit from transmitting and receiving wireless communications via the first antenna to transmitting and receiving wireless communications via the second antenna in response to detecting:
a first receive power level of the first antenna is less than a second receive power level of the second antenna;
a difference between the second receive power level and the first receive power level is greater than a first threshold; and
the difference between the second receive power level and the first receive power level added to a difference between a second transmit power limit of the second antenna and a first transmit power limit of the first antenna is greater than a second threshold.

2. The wireless communication apparatus of claim 1 , wherein the first threshold is based on a difference between the first receive power level and a thermal noise limit.

3. The wireless communication apparatus of claim 2 , wherein the first threshold is obtained via a look up table indexed by the first receive power level.

4. The wireless communication apparatus of claim 1 , wherein the second threshold is based on a difference between the first receive power level and a thermal noise limit.

5. The wireless communication apparatus of claim 1 , wherein the controller is configured to reset a pilot filter in response to switching the transmit circuit and the receive circuit to transmit and receive wireless communications via the second antenna.

6. The wireless communication apparatus of claim 1 , wherein the controller is configured to disregard reverse link power control commands for adjusting transmit power levels during a time interval in response to switching the transmit circuit and the receive circuit to transmit and receive wireless communications via the second antenna.

7. The wireless communication apparatus of claim 1 , wherein the controller is configured to transmit and receive wireless communications via the second antenna before a time interval begins in which the controller is configured to search for pilots signals in an active pilot set.

8. The wireless communication apparatus of claim 1 , wherein the receive circuit is a first receive circuit, wherein the wireless communication apparatus comprises a second receive circuit configured to receive wireless communications using either the first antenna or the second antenna, and wherein the controller comprises a measurement circuit configured to:
sample a first automatic gain control measurement using either the first receive circuit or the second receive circuit that is connected to the first antenna at a predetermined time interval;
sample a second automatic gain control measurement using either the first receive circuit or the second receive circuit that is connected to the second antenna at the predetermined time interval;
filter the first automatic gain control measurement using a first single pole infinite impulse response (IIR) filter, wherein the first receive power level is based on the filtered first automatic gain control measurement; and
filter the second automatic gain control measurement using a second single pole infinite impulse response (IIR) filter, wherein the second receive power level is based on the filtered second automatic gain control measurement.

9. The wireless communication apparatus of claim 1 , wherein a default configuration corresponds to when the transmit circuit and the receive circuit are configured to transmit and receive via the first antenna, and wherein the controller is configured to switch to the default configuration if the first receive power level and the second receive power level are below a receive power level threshold.

10. The wireless communication apparatus of claim 1 , wherein the transmit circuit comprises one or more components forming a transmit chain for transmitting wireless communications based on a radio access technology type, and wherein the receive circuit comprises one or more other components forming a receive chain for receiving wireless communications based on the radio access technology type.

11. A method of wireless communications, comprising:
receiving an indication of a first receive power level of a first antenna and a second receive power level of a second antenna; and
switching a transmit circuit and a receive circuit from transmitting and receiving wireless communications via the first antenna to transmit and receive wireless communications via the second antenna in response to detecting:
a first receive power level of the first antenna is less than a second receive power level of the second antenna;
a difference between the second receive power level and the first receive power level is greater than a first threshold; and
the difference between the second receive power level and the first receive power level added to a difference between a second transmit power limit of the second antenna and a first transmit power limit of the first antenna is greater than a second threshold.

12. The method of claim 11 , further comprising determining the first threshold based on a difference between the first receive power level and a thermal noise limit.

13. The method of claim 12 , wherein determining the first threshold comprises determining the first threshold via a look up table indexed by the first receive power level.

14. The method of claim 11 , further comprising determining the second threshold based on a difference between the first receive power level and a thermal noise limit.

15. The method of claim 11 , further comprising resetting a pilot signal filter in response to switching the transmit circuit and the receive circuit to transmit and receive wireless communications via the second antenna.

16. The method of claim 11 , further comprising disregarding reverse link power control commands for adjusting transmit power levels during a time interval in response to switching the transmit circuit and the receive circuit to transmit and receive wireless communications via the second antenna.

17. The method of claim 11 , further comprising performing a search for pilot signals in an active pilot set in response to switching.

18. The method of claim 11 , wherein the receive circuit is a first receive circuit and wherein receiving an indication of a first receive power level and a second receive power level comprises determining the first power level and the second power level, comprising:
sampling a first automatic gain control measurement using either the first receive circuit or a second receive circuit that is connected to the first antenna at a predetermined time interval;
sampling a second automatic gain control measurement using either the first receive circuit or the second receive circuit that is connected to the second antenna at the predetermined time interval;
filtering the first automatic gain control measurement using a first single pole infinite impulse response (IIR) filter, wherein the first receive power level is based on the filtered first automatic gain control measurement; and
filtering the second automatic gain control measurement using a second single pole infinite impulse response (IIR) filter, wherein the second receive power level is based on the

Assignees

• Qualcomm Inc

Inventors

• Ngai Francis Ming-Meng
• Attar Rashid Ahmed Akbar
• Filipovic Daniel Fred
• Ghosh Donna
• Lott Christopher Gerard
• Hu Jun

Classifications

• H04B7/0814

  based on current reception conditions, e.g. switching to different antenna when signal level is below threshold · CPC title

• H04B7/0604

  with predefined switching scheme · CPC title

• H04W88/00

  Devices specially adapted for wireless communication networks, e.g. terminals, base stations or access point devices · CPC title

• H04B7/0817

  with multiple receivers and antenna path selection · CPC title

• H04B7/0608 Primary

  Antenna selection according to transmission parameters · CPC title