Apparatus and method for selecting modulation and filter roll-off to meet power and bandwidth requirements

• US 20070218942A1
• Filed: 01/29/2007
• Published: 09/20/2007
• Est. Priority Date: 03/17/2006
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Khan, Farooq, Tsai, Jiann-An
• Granted Patent: US 7,924,775 B2
• Time in Patent Office: Days
• US Class Current: 455/553.100
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/0025 Transmission of mode-switching indication
• CPC Class Codes: H04L 25/03834 using pulse shaping
• CPC Class Codes: H04L 27/2614 Peak power aspects
• CPC Class Codes: H04L 27/2626 Arrangements specific to the transmitter only
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0046 Determination of how many bits are transmitted on different sub-channels
• CPC Class Codes: H04L 5/0058 Allocation criteria

Abstract

A base station for use in a wireless network that communicates according to a multi-carrier protocol. The base station receives an uplink signal transmitted by a first subscriber station. The first subscriber station transmits using a configurable spectral shaping filter and a selectable modulation order. The base station determines a required bandwidth efficiency associated with the first subscriber station and, in response to the determination, selects a first modulation order and a first filter parameter to be used by the first subscriber station. Advantageously, the base station selects the first modulation order and the first filter parameter in order to maximize a power efficiency of the first subscriber station while maintaining the required bandwidth efficiency.

Claims

1. For use in a wireless network capable of communicating with a plurality of subscriber stations according to a multi-carrier protocol, a base station operable to receive an uplink signal transmitted by a first subscriber station, the first subscriber station capable of transmitting in the uplink using a configurable spectral shaping filter and using a plurality of selectable modulation orders, wherein the base station determines a required bandwidth efficiency associated with the first subscriber station and, in response to the determination, selects a first modulation order to be used by the first subscriber station to transmit in the uplink.

2. The base station as set forth in claim 1, wherein the base station selects the first modulation order in order to maximize a power efficiency of the first subscriber station while maintaining the required bandwidth efficiency.

3. The base station as set forth in claim 1, wherein the base station further selects a first filter parameter to be used to configure the spectral shaping filter in the first subscriber station.

4. The base station as set forth in claim 3, wherein the base station selects the first modulation order and the first filter parameter in order to maximize a power efficiency of the first subscriber station while maintaining the required bandwidth efficiency.

5. The base station as set forth in claim 3, wherein the base station further selects a channel coding rate to be used by the first subscriber station to transmit in the uplink.

6. The base station as set forth in claim 5, wherein the base station selects the first modulation order, the first filter parameter, and the channel coding rate in order to maximize a power efficiency of the first subscriber station while maintaining the required bandwidth efficiency.

7. The base station as set forth in claim 5, wherein the base station selects the first modulation order, the first filter parameter, and the channel coding rate in order to provide an optimum tradeoff between power efficiency and bandwidth efficiency in the first subscriber station.

8. For use in a wireless network capable of communicating with a plurality of subscriber stations according to a multi-carrier protocol, a method of communicating in an uplink between a base station and a first subscriber station, the first subscriber station capable of transmitting in the uplink using a configurable spectral shaping filter and using a plurality of selectable modulation orders, the method comprising the steps of:

determining a required bandwidth efficiency associated with the first subscriber station; and

in response to the determination, selecting a first modulation order to be used by the first subscriber station to transmit in the uplink.

9. The method as set forth in claim 8, wherein the step of selecting the first modulation order maximizes a power efficiency of the first subscriber station while maintaining the required bandwidth efficiency.

10. The method as set forth in claim 8, further comprising the step of selecting a first filter parameter to be used to configure the spectral shaping filter in the first subscriber station.

11. The method as set forth in claim 10, wherein the steps of selecting the first modulation order and selecting the first filter parameter maximize a power efficiency of the first subscriber station while maintaining the required bandwidth efficiency.

12. The method as set forth in claim 10, further comprising the step of selecting a channel coding rate to be used by the first subscriber station to transmit in the uplink.

13. The method as set forth in claim 12, wherein the steps of selecting the first modulation order, selecting the first filter parameter, and selecting the channel coding rate maximize a power efficiency of the first subscriber station while maintaining the required bandwidth efficiency.

14. For use in a wireless network capable of communicating with a plurality of subscriber stations according to a multi-carrier protocol, a base station operable to receive an uplink signal transmitted by a first subscriber station, the first subscriber station capable of transmitting in the uplink using a configurable spectral shaping filter and using a plurality of selectable modulation orders, wherein the base station determines a required power efficiency associated with the first subscriber station and, in response to said determination, selects a first modulation order to be used by the first subscriber station to transmit in the uplink.

15. The base station as set forth in claim 14, wherein the base station selects the first modulation order in order to maximize a bandwidth efficiency of the first subscriber station while maintaining the required power efficiency.

16. The base station as set forth in claim 14, wherein the base station further selects a first filter parameter to be used to configure the spectral shaping filter in the first subscriber station.

17. The base station as set forth in claim 16, wherein the base station selects the first modulation order and the first filter parameter in order to maximize a bandwidth efficiency of the first subscriber station while maintaining the required power efficiency.

18. The base station as set forth in claim 16, wherein the base station further selects a channel coding rate to be used by the first subscriber station to transmit in the uplink.

19. The base station as set forth in claim 18, wherein the base station selects the first modulation order, the first filter parameter, and the channel coding rate in order to maximize a bandwidth efficiency of the first subscriber station while maintaining the required power efficiency.

20. The base station as set forth in claim 18, wherein the base station selects the first modulation order, the first filter parameter, and the channel coding rate in order to provide an optimum tradeoff between power efficiency and bandwidth efficiency in the first subscriber station.

21. For use in a wireless network capable of communicating with a plurality of subscriber stations according to a multi-carrier protocol, a method of communicating in an uplink between a base station and a first subscriber station, the first subscriber station capable of transmitting in the uplink using a configurable spectral shaping filter and using a plurality of selectable modulation orders, the method comprising the steps of:

determining a required power efficiency associated with the first subscriber station; and

in response to the determination, selecting a first modulation order to be used by the first subscriber station to transmit in the uplink.

22. The method as set forth in claim 21, wherein the step of selecting the first modulation order maximizes a bandwidth efficiency of the first subscriber station while maintaining the required power efficiency.

23. The method as set forth in claim 21, further comprising the step of selecting a first filter parameter to be used to configure the spectral shaping filter in the first subscriber station.

24. The method as set forth in claim 23, wherein the steps of selecting the first modulation order and selecting the first filter parameter maximize a bandwidth efficiency of the first subscriber station while maintaining the required power efficiency.

25. The method as set forth in claim 23, further comprising the step of selecting a channel coding rate to be used by the first subscriber station to transmit in the uplink.

26. The method as set forth in claim 25, wherein the steps of selecting the first modulation order, selecting the first filter parameter, and selecting the channel coding rate maximize a bandwidth efficiency of the first subscriber station while maintaining the required power efficiency.