TRANSMISSION POWER REDUCTION FOR CO-EXISTENCE ON A SHARED COMMUNICATION MEDIUM

• US 20160095040A1
• Filed: 09/22/2015
• Published: 03/31/2016
• Est. Priority Date: 09/26/2014
• Status: Abandoned Application

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: VALLIAPPAN, Nachiappan, KADOUS, Tamer Adel, SADEK, Ahmed Kamel
• Application Number:
  US14/861,872
• Publication Number:
  US 20160095040A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04L 5/0044 allocation of payload
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 36/14 Reselecting a network or an air interface
• CPC Class Codes: H04W 36/30 by measured or perceived connection quality data
• CPC Class Codes: H04W 52/242 taking into account path loss
• CPC Class Codes: H04W 52/246 where the output power of a terminal is based on a path parameter calculated in said terminal
• CPC Class Codes: H04W 52/44 in connection with interruption of transmission
• CPC Class Codes: H04W 76/28 Discontinuous transmission [DTX]; Discontinuous reception [DRX]
• CPC Class Codes: H04W 88/10 adapted for operation in multiple networks, e.g. multi-mode access points

Abstract

Techniques for co-existence on a shared communication medium are disclosed. In one example, transmission in accordance with a first Radio Access Technology (RAT) may be punctured on one or more active periods of a Discontinuous Transmission (DTX) communication pattern based on monitoring of signaling associated with a second RAT. In addition or as an alternative, a transmission power level of an access point for transmission in accordance with a first RAT may be reduced based on one or more signal timing characteristics of signaling associated with a second RAT.

Claims

1. A communication method, comprising:

transmitting a first signal at a first transmission power level and in accordance with a first Radio Access Technology (RAT) on a communication medium shared with a second RAT;

monitoring second RAT signaling on the communication medium for one or more signal timing characteristics;

reducing the first transmission power level to a second transmission power level based on the one or more signal timing characteristics; and

transmitting a second signal at the second transmission power level and in accordance with the first RAT on the communication medium.

2. The method of claim 1, the one or more signal timing characteristics being indicative of a timing delay associated with (i) a beacon inter-arrival periodicity or (ii) a probe request and probe response pair.

3. The method of claim 2, further comprising iteratively repeating the monitoring and the reducing until the timing delay ceases.

4. The method of claim 1, further comprising:

calculating a path loss associated with the second RAT signaling; and

computing the second transmission power level based on the path loss and a backoff threshold defined by the second RAT for accessing the communication medium.

5. The method of claim 4, the backoff threshold corresponding to a Clear Channel Assessment Energy Detection (CCA-ED) threshold.

6. The method of claim 4, the calculating comprising:

measuring a received signaling energy of the second RAT signaling;

estimating a transmission power associated with the second RAT signaling; and

calculating the path loss based on the received signaling energy and the associated transmission power.

7. The method of claim 6, the estimating comprising reading from the second RAT signaling (i) a Transmit Power Control (TPC) Report Information Element (IE) or (ii) a country or local power constraint IE.

8. The method of claim 4, the calculating comprising:

transmitting a series of probe request messages in accordance with the second RAT at decreasing transmission power levels;

monitoring probe response messages to assess decoding success or failure of the probe request messages;

determining a minimum transmission power for successful decoding of the probe request messages based on the monitoring; and

determining the path loss based on the minimum transmission power and an associated transmission power requirement for successful decoding.

9. The method of claim 1, further comprising:

cycling operation of the first RAT between active periods and inactive periods of transmission on the communication medium in accordance with a Discontinuous Transmission (DTX) communication pattern,

the transmitting of the second signal at the second transmission power level and in accordance with the first RAT aligning with one or more of the active periods of the DTX communication pattern.

10. The method of claim 1:

the communication medium comprising one or more time, frequency, or space resources on an unlicensed radio frequency band;

the first RAT comprising Long Term Evolution (LTE) technology; and

the second RAT comprising Wi-Fi technology.

11. A communication apparatus, comprising:

a first transceiver configured to transmit a first signal at a first transmission power level and in accordance with a first Radio Access Technology (RAT) on a communication medium shared with a second RAT;

a second transceiver configured to monitor second RAT signaling on the communication medium for one or more signal timing characteristics;

at least one processor; and

at least one memory coupled to the at least one processor, the at least one processor and the at least one memory being configured to reduce the first transmission power level to a second transmission power level based on the one or more signal timing characteristics,

the first transceiver being further configured to transmit a second signal at the second transmission power level and in accordance with the first RAT on the communication medium.

12. The apparatus of claim 11, the one or more signal timing characteristics being indicative of a timing delay associated with (i) a beacon inter-arrival periodicity or (ii) a probe request and probe response pair.

13. The apparatus of claim 12, the second transceiver and the at least one processor and the at least one memory being further configured to iteratively repeat the monitoring and the reducing until the timing delay ceases.

14. The apparatus of claim 11, the at least one processor and the at least one memory being further configured to:

calculate a path loss associated with the second RAT signaling; and

compute the second transmission power level based on the path loss and a backoff threshold defined by the second RAT for accessing the communication medium.

15. The apparatus of claim 14, the backoff threshold corresponding to a Clear Channel Assessment Energy Detection (CCA-ED) threshold.

16. The apparatus of claim 14, the at least one processor and the at least one memory being configured to calculate the path loss by:

measuring a received signaling energy of the second RAT signaling;

estimating a transmission power associated with the second RAT signaling; and

calculating the path loss based on the received signaling energy and the associated transmission power.

17. The apparatus of claim 16, the at least one processor and the at least one memory being configured to estimate the transmission power by reading from the second RAT signaling (i) a Transmit Power Control (TPC) Report Information Element (IE) or (ii) a country or local power constraint IE.

18. The apparatus of claim 14, the at least one processor and the at least one memory being configured to calculate the path loss by:

transmitting a series of probe request messages in accordance with the second RAT at decreasing transmission power levels;

monitoring probe response messages to assess decoding success or failure of the probe request messages;

determining a minimum transmission power for successful decoding of the probe request messages based on the monitoring; and

determining the path loss based on the minimum transmission power and an associated transmission power requirement for successful decoding.

19. The apparatus of claim 11, the first transceiver being further configured to:

cycle operation of the first RAT between active periods and inactive periods of transmission on the communication medium in accordance with a Discontinuous Transmission (DTX) communication pattern; and

align the transmitting of the second signal at the second transmission power level and in accordance with the first RAT with one or more of the active periods of the DTX communication pattern.

20. The apparatus of claim 11:

the communication medium comprising one or more time, frequency, or space resources on an unlicensed radio frequency band;

the first RAT comprising Long Term Evolution (LTE) technology; and

the second RAT comprising Wi-Fi technology.

21. A communication apparatus, comprising:

means for transmitting a first signal at a first transmission power level and in accordance with a first Radio Access Technology (RAT) on a communication medium shared with a second RAT;

means for monitoring second RAT signaling on the communication medium for one or more signal timing characteristics;

means for reducing the first transmission power level to a second transmission power level based on the one or more signal timing characteristics; and

means for transmitting a second signal at the second transmission power level and in accordance with the first RAT on the communication medium.

22. The apparatus of claim 21, the one or more signal timing characteristics being indicative of a timing delay associated with (i) a beacon inter-arrival periodicity or (ii) a probe request and probe response pair, and the apparatus further comprising means for iteratively repeating the monitoring and the reducing until the timing delay ceases.

23. The apparatus of claim 21, further comprising:

means for calculating a path loss associated with the second RAT signaling; and

means for computing the second transmission power level based on the path loss and a backoff threshold defined by the second RAT for accessing the communication medium.

24. The apparatus of claim 23, the means for calculating comprising:

means for measuring a received signaling energy of the second RAT signaling;

means for estimating a transmission power associated with the second RAT signaling; and

means for calculating the path loss based on the received signaling energy and the associated transmission power.

25. The apparatus of claim 23, the means for calculating comprising:

means for transmitting a series of probe request messages in accordance with the second RAT at decreasing transmission power levels;

means for monitoring probe response messages to assess decoding success or failure of the probe request messages;

means for determining a minimum transmission power for successful decoding of the probe request messages based on the monitoring; and

means for determining the path loss based on the minimum transmission power and an associated transmission power requirement for successful decoding.

26. A non-transitory computer-readable medium, comprising:

code for transmitting a first signal at a first transmission power level and in accordance with a first Radio Access Technology (RAT) on a communication medium shared with a second RAT;

code for monitoring second RAT signaling on the communication medium for one or more signal timing characteristics;

code for reducing the first transmission power level to a second transmission power level based on the one or more signal timing characteristics; and

code for transmitting a second signal at the second transmission power level and in accordance with the first RAT on the communication medium.

27. The non-transitory computer-readable medium of claim 26, the one or more signal timing characteristics being indicative of a timing delay associated with (i) a beacon inter-arrival periodicity or (ii) a probe request and probe response pair, and the non-transitory computer-readable medium further comprising code for iteratively repeating the monitoring and the reducing until the timing delay ceases.

28. The non-transitory computer-readable medium of claim 26, further comprising:

code for calculating a path loss associated with the second RAT signaling; and

code for computing the second transmission power level based on the path loss and a backoff threshold defined by the second RAT for accessing the communication medium.

29. The non-transitory computer-readable medium of claim 28, the code for calculating comprising:

code for measuring a received signaling energy of the second RAT signaling;

code for estimating a transmission power associated with the second RAT signaling; and

code for calculating the path loss based on the received signaling energy and the associated transmission power.

30. The non-transitory computer-readable medium of claim 28, the code for calculating comprising:

code for transmitting a series of probe request messages in accordance with the second RAT at decreasing transmission power levels;

code for monitoring probe response messages to assess decoding success or failure of the probe request messages;

code for determining a minimum transmission power for successful decoding of the probe request messages based on the monitoring; and

code for determining the path loss based on the minimum transmission power and an associated transmission power requirement for successful decoding.