Systems and etiquette for home gateways using white space

• US 8,107,391 B2
• Filed: 11/19/2008
• Issued: 01/31/2012
• Est. Priority Date: 11/19/2008
• Status: Expired due to Fees

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Quarterhill Inc. (f/k/a Wi-LAN Inc.)
• Inventors: Wu, Shiquan, Yee, Jung
• Primary Examiner(s): Phillips, Hassan
• Assistant Examiner(s): Cattungal, Ajay
• Application Number:
  US12/274,141
• Publication Number:
  US 20100124254A1
• Time in Patent Office: 1,168 Days
• Field of Search: None
• US Class Current: 370/252
• CPC Class Codes: H04L 27/2602 Signal structure
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/003 Arrangements for allocating sub-channels of the transmission path
• CPC Class Codes: H04W 16/02 Resource partitioning among network components, e.g. reuse partitioning
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 88/16 Gateway arrangements

Abstract

Methods and systems for sharing white space with primary services and other emerging services are provided. Signal distribution within a specified location, such as a dwelling, is performed using a home gateway that identifies unused white space, reserves such white space spectrum, and delivers data to one or more devices at the respective location using the reserved spectrum. Signalling between the devices and the gateway is performed over a shared signalling channel, which enables the gateway to advise the devices from where and when to receive data. The gateway also uses a common spectrum reservation OFDM symbol to advise the neighboring gateways of the local spectrum reservation.

Claims

1. A gateway system for redistributing data signals to wireless enabled devices located within a specified area, comprising:

a backhaul interface adapted to communicate with a backhaul communication connection to receive information signals for distribution to a plurality of wireless enabled devices served by the gateway system;

a spectrum detector for identifying a white space channel including one or more pieces of spectrum that are not currently used in the specified area;

a data distribution unit in communication with the backhaul interface and adapted to receive, process and distribute to the wireless enabled devices served by the gateway system, the information signals received from the backhaul interface, the distribution occurring over the white space channel;

and

a control channel processor for providing a shared signalling channel for enabling control signalling between the wireless enabled device and the data distribution unit.

2. A system as claimed in claim 1, wherein the control channel processor selects a carrier for the shared signalling channel within a portion of the white space available at the specified location.

3. A system as claimed in claim 1, wherein the control channel processor selects a carrier for the shared signalling channel within a specified portion of white space available in the specified location.

4. A system as claimed in claim 3, wherein the specified portion of white space is within the spectrum reserved for one of the ATSC channels 2, 3 and 4.

5. A system as claimed in claim 3, wherein the specified portion of white space is within the spectrum reserved for one of ATSC channels unused in the specified area.

6. A system as claimed in claim 2, wherein the carrier frequency of the shared signalling channel is selected in a fixed relationship with the beginning of an ATSC channel.

7. A system as claimed in claim 1, wherein the control signal processor determines the bandwidth of the shared signalling channel based on the number of the devices served by the data distribution unit.

8. A system as claimed in claim 7, wherein the bandwidth of the shared signalling channel is 300 kHz.

9. A system as claimed in claim 1, wherein the control signal processor regularly broadcasts downlink messages over the shared signalling channel to the devices it currently serves.

10. A system as claimed in claim 9, wherein the downlink messages are carried in a TDD frame.

11. A system as claimed in claim 10, wherein a downlink message provides a respective device with access information.

12. A system as claimed in claim 10, wherein a downlink message provides a respective device with frequency and time information for enabling the device to receive the information signals distributed by the data distribution unit.

13. A system as claimed in claim 1, wherein the devices share an uplink frame transmitted on the shared signalling channel.

14. A system as claimed in claim 13, wherein the uplink messages are carried in a TDD frame.

15. A system as claimed in claim 14, wherein an uplink message transmitted by a respective device includes access request data.

16. A system as claimed in claim 1, wherein, upon establishing a connection with a device, the data distribution unit reserves the white space channel for the duration of the connection.

17. A system of claim 16, wherein the data distribution unit broadcasts at predetermined intervals of time a spectrum reservation symbol with information about the white space spectrum reserved for communication with the devices it serves.

18. A system as claimed in claim 17, wherein the spectrum reservation symbol is an common spectrum reservation OFDM symbol to all data distribution units operating in the neighborhood of the specified location.

19. A system as claimed in claim 18, wherein the spectrum reservation symbol uses a sub-carrier spacing Δ

f=200 kHz and a discrete Fourier transform size N=1370.

20. A system as claimed in claim 18, wherein the data distribution unit transmits a bit map on the spectrum it reserved.

21. A system as claimed in claim 18, wherein the data distribution unit begins distribution of the information signal to a device using a designated time and frequency grid.

22. A system as claimed in claim 17, wherein the white space spectrum reserved by the data distribution unit is advertised through the spectrum reservation symbol using a bin indexing scheme.

23. A system as claimed in claim 22, wherein the bin indexing scheme identifies the white space portions within the spectrum reserved for DTV broadcast.

24. A system as claimed in claim 23, wherein the bin indexing scheme identifies the white space using an index for each of the four pieces of spectrum T2-T5.

25. A system as claimed in claim 24, wherein the bin indexing scheme addresses the bandwidth reserved for a ATSC channel using 30 bins.

26. A method of operating a gateway for redistributing data signals from the gateway to a plurality of wireless enabled devices located within a specified area, comprising:

a) establishing by the gateway, on start on, a shared signalling channel over a piece of spectrum that is not currently used in the specified area;

b) on receipt of a service request from a wireless enabled device transmitted over the shared signalling channel, the gateway establishing a white space channel using one or more pieces of spectrum that are not currently used in the specified area;

c) receiving at the gateway, over a back haul connection, an information signal responsive to the service request;

d) distributing the information signal over the white space channel to the wireless enabled device; and

e) controlling transfer of the information signal to the wireless enabled device by exchanging control messages over the shared signalling channel.

27. A method as claimed in claim 26, wherein step a) comprises:

scanning a selected part of the spectrum for identifying the piece of spectrum; and

selecting a carrier frequency for the shared signalling channel in a pre-selected relationship with a frequency mark defined by the ATSC specification.

28. A method as claimed in claim 27, wherein the selected part of the spectrum is specified within a certain relationship with an ATSC channel.

29. A method as claimed in claim 26, wherein step e) comprises transmitting to the wireless enabled device on the signalling channel a downlink control message with the parameters of the white space channel, for enabling the wireless enabled device to receive the information signal starting from a designated time and on a designated frequency.

30. A method as claimed in claim 29, wherein the parameters of the white space channel comprise the carrier frequency, start time and the bandwidth.

31. A method as claimed in claim 29, wherein the parameters of the white space channel are transmitted to the wireless enabled device in the form of a bit map.

32. A method as claimed in claim 29, wherein the downlink control message with the parameters of the white space channel is provided in the form of a frequency-time grid specifying a time interval to be used by the wireless enabled device for data transmission and the frequency band to be used during the time interval.

33. A method as claimed in claim 26, wherein the bandwidth of the shared signalling channel is 500 kHz.

34. A method as claimed in claim 26, wherein the shared signalling channel is a TDD channel.

35. A method of operating a gateway for redistributing data signals to wireless enabled devices located within a specified area served by a gateway, comprising:

a) on receipt at a gateway of service requests from one or more devices, the gateway identifying a corresponding number of white space channels within the spectrum that is not currently used in the specified area;

b) reserving the white space allocated to the white space channels identified in the specified area;

c) broadcasting by the gateway a white space allocation message for advertising to all neighboring gateways the current channel allocation in the specified area;

d) receiving by the gateway, over a back haul connection, information signals responsive to the service requests; and

e) distributing the information signals over the white space channels to the respective devices.

36. A method as claimed in claim 35, wherein the white space allocation data is broadcast in the form of a common spectrum reservation OFDM symbol.

37. A method as claimed in claim 36, wherein the common spectrum reservation OFDM symbol uses a sub-carrier spacing Δ

f=200 kHz, and a size N of the Fourier transform N=1370.

38. A method as claimed in claim 35, wherein the white space allocation message identifies the reserved spectrum using a bin indexing scheme.

39. A system as claimed in claim 38, wherein the bin indexing scheme identifies the white space using an index for each of the four pieces of spectrum T2-T5.

40. A system as claimed in claim 38, wherein the bin indexing scheme addresses the bandwidth reserved for an ATSC channel using 30 bins.