Channel optimization in half duplex communications systems

• US 9,504,049 B2
• Filed: 07/07/2014
• Issued: 11/22/2016
• Est. Priority Date: 01/24/2014
• Status: Active Grant

• Current Assignee: Mimosa Networks, Inc. (Airspan Networks Inc.)
• Original Assignee: Mimosa Networks, Inc. (Airspan Networks Inc.)
• Inventors: Hinman, Brian, Gurevich, David, Keskinen, Miika, Ponnampalam, Vishakan, Wong, Chiu Ngok Eric
• Primary Examiner(s): Kizou, Hassan
• Assistant Examiner(s): DAYA, TEJIS A
• Application Number:
  US14/325,307
• Publication Number:
  US 20150215952A1
• Time in Patent Office: 869 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: H04L 27/0006 Assessment of spectral gaps suitable for allocating digitally modulated signals, e.g. for carrier allocation in cognitive radio for spectrum sharing between different networks H04W16/14
• CPC Class Codes: H04L 5/0033 each allocating device acting autonomously, i.e. without negotiation with other allocating devices
• CPC Class Codes: H04L 5/16 Half-duplex systems; Simplex/duplex switching; Transmission of break signals non-automatically inverting the direction of transmission
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 72/542 using measured or perceived quality

Abstract

Channel Optimization in Half Duplex Communications Systems is provided herein. Methods may include obtaining at a first terminal, radio frequency (RF) spectral information local to the first terminal, analyzing at the first terminal, RF spectral information for a second terminal that is not co-located with the first terminal, transmitting data to the second terminal on a second terminal optimal frequency band, and receiving data from the second terminal on the first terminal optimal frequency band, where the first terminal optimal frequency being based upon the RF spectral information local to the first terminal.

Claims

1. A method for transmitting data between network devices using channel optimization in half duplex communications, the method comprising:

obtaining at a first terminal, radio frequency (RF) spectral information local to the first terminal;

determining at the first terminal a first terminal optimal frequency band for the first terminal from the RF spectral information;

transmitting to a second terminal the first terminal optimal frequency band for use by the second terminal when transmitting data to the first terminal, the second terminal not being co-located with the first terminal;

receiving from the second terminal any of;

RF spectral information local to the second terminal; and

a second terminal optimal frequency band;

if receiving RF spectral information local to the second terminal;

determining the second terminal optimal frequency band using the RF spectral information for the second terminal;

transmitting data to the second terminal on the second terminal optimal frequency band; and

receiving data from the second terminal on the first terminal optimal frequency band.

2. The method according to claim 1, wherein the first terminal and the second terminal each determine their respective RF spectral information by any of:

scanning the local RF spectral information on a periodic basis;

scanning the local RF spectral information upon determining a loss of signal quality; and

upon receiving a request from a network device to scan for the local RF spectral information, wherein the first and the second terminals are network devices.

3. The method according to claim 1, wherein the first terminal optimal frequency band includes a frequency band having maximum available throughput for a wireless link established between the first terminal and the second terminal, as determined from analysis of local RF spectral information.

4. The method according to claim 1, wherein the first terminal optimal frequency band and the second terminal optimal frequency band are different from one another.

5. The method according to claim 1, further comprising any of:

transmitting, by the first terminal, the radio frequency (RF) spectral information for the first terminal; and

receiving, by the first terminal, the radio frequency (RF) spectral information for the second terminal.

6. The method according to claim 5, further comprising analyzing the radio frequency (RF) spectral information for the second terminal to determine the second terminal optimal frequency band.

7. The method according to claim 1, further comprising encapsulating the radio frequency (RF) spectral information for the first terminal in a management frame and transmitting the management frame over a wireless link to additional terminals.

8. The method according to claim 1, further comprising receiving from the second terminal the second terminal optimal frequency band for the second terminal.

9. A network coordinator for a network using time division duplexing or time division multiple access, the network coordinator comprising:

a processor; and

a memory for storing executable instructions, the processor executing the instructions to perform operations comprising;

establishing a wireless link with a plurality of terminal devices;

receiving from the plurality of terminal devices, radio frequency (RF) spectral information;

exchanging the RF spectral information between the plurality of terminal devices; and

negotiating a frequency band for each of the plurality of terminal devices such that a product or a sum of a forward link and a reverse link throughput for each of the plurality of terminal devices is jointly maximized on the wireless link, the forward and reverse link throughput being determined from an analysis of the radio frequency (RF) spectral information for the plurality of terminal devices.

10. The network coordinator according to claim 9, wherein the processor further executes the instructions to perform an operation of requesting updated radio frequency (RF) spectral information from one or more of the plurality of terminal devices when the network coordinator determines that a degradation in signal strength of the one or more of the plurality of terminal devices has exceeded a threshold.

11. The network coordinator according to claim 9, wherein the processor further executes the instructions to perform an operation of assigning a transmission period to each of the plurality of terminal devices.

12. The network coordinator according to claim 11, wherein the plurality of terminal devices operates in half-duplex mode using any of carrier sensing and token exchange rather than requiring the network coordinator to assign transmission periods to the plurality of terminal devices.

13. The network coordinator according to claim 9, wherein at least a portion of the plurality of terminal devices transmit a preferred frequency band in lieu of or in addition to RF spectral information.

14. The network coordinator according to claim 9, wherein the processor further executes the instructions to perform an operation of renegotiating a frequency band for each of the plurality of terminal devices when updated RF spectral information is received from at least one of the plurality of terminal devices.

15. The network coordinator according to claim 9, wherein the network coordinator is a point-to-point device that supports communication between two or more terminal devices or a point-to-multipoint device that supports communication between a first terminal device and a plurality of other terminal devices.

16. The network coordinator according to claim 9, wherein the network coordinator creates management frame for each of the plurality of terminal devices, wherein each management frame for each of the plurality of terminal devices includes an optimal receiving frequency and a plurality of optimal transmitting frequencies.

17. A terminal device, comprising:

a processor; and

a memory for storing executable instructions, wherein execution of the instructions causes the processor to;

determine radio frequency (RF) spectral information local to the terminal device;

analyze RF spectral information for one or more additional terminal devices in a network that are not co-located with the terminal device;

determine an optimal frequency band for each of the one or more additional terminal devices;

transmit data to the one or more additional terminal devices using the determined optimal frequency bands; and

receive data from the one or more additional terminal devices on a device optimal frequency band that is based upon the RF spectral information local to the terminal device.

18. The terminal device according to claim 17, wherein the terminal device informs the one or more additional terminal devices of the device optimal frequency band by transmitting the device optimal frequency band to a network coordinator.

19. The terminal device according to claim 17, wherein the terminal device determines the RF spectral information by any of:

scanning the local RF spectral information on a periodic basis;

scanning the local RF spectral information upon determining a loss of signal quality; and

upon receiving a request from a network device to scan for local RF spectral information, wherein the network device includes any of a network coordinator or the one or more additional terminal devices.

20. The terminal device according to claim 17, wherein the optimal frequency band includes a frequency band having maximum available throughput for a wireless link, as determined from analysis of local RF spectral information.

21. The terminal device according to claim 17, wherein the device determined optimal frequency band and the one or more additional device optimal frequency bands are different from one another.

22. The terminal device according to claim 17, wherein the terminal device is further configured to:

transmit the radio frequency (RF) spectral information for the terminal device to the one or more additional terminal devices; and

receive radio frequency (RF) spectral information for the one or more additional terminal devices.

23. The terminal device according to claim 22, wherein the terminal device is further configured to request updated RF spectral information from the one or more additional terminal devices.

24. The terminal device according to claim 17, wherein the terminal device is further configured to:

encapsulate the radio frequency (RF) spectral information in a management frame; and

transmit the management frame over a wireless link to the one or more additional terminal devices.

25. The terminal device according to claim 17, wherein the terminal device is further configured to receive from at least a portion of the one or more additional terminal devices, a desired optimal frequency band in lieu of the RF spectral information.

26. The terminal device according to claim 17, wherein the device optimal frequency band is selected at the terminal device by analyzing the RF spectral information for the terminal device to determine a signal-to-noise ratio, an error vector magnitude, an interference plus noise power spectrum, or an overlapping basic service set traffic activity.