Rate dependent transmission gain control for WLAN systems

• US 20050215258A1
• Filed: 10/14/2004
• Published: 09/29/2005
• Est. Priority Date: 03/25/2004
• Status: Active Grant

• Current Assignee: Advanced Micro Devices, Inc.
• Original Assignee: Advanced Micro Devices, Inc.
• Inventors: Beyer, Sascha, Schmidt, Michael, Hanusch, Thomas
• Granted Patent: US 7,349,709 B2
• Time in Patent Office: Days
• US Class Current: 455/452.100
• CPC Class Codes: H04B 1/04 Circuits
• CPC Class Codes: H04B 2001/0416 having gain or transmission power control
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

A WLAN (Wireless Local Area Network) transmission technique is provided where data is transmitted in two or more different transmission modes at different transmission rates. A transmission gain is determined to be applied when transmitting data. The transmission gain is determined to be transmission mode dependent such that the transmission gain in a first transmission mode is greater than the transmission gain in a second transmission mode if the transmission rate in the first transmission mode is lower than the transmission rate in the second transmission mode.

Claims

1. A WLAN (Wireless Local Area Network) transmitter device capable of transmitting data in two or more different transmission modes at different transmission rates, comprising:

a transmission gain controller for determining a transmission gain to be applied when transmitting data; and

a data transmission section for transmitting data at a transmission gain determined by said transmission gain controller,

wherein said transmission gain determined by said transmission gain controller is transmission mode dependent, with the transmission gain applied in a first one of said two or more different transmission modes being greater that the transmission gain applied in a second one of said two or more different transmission modes if the transmission rate in said first one of said two or more different transmission modes is smaller than the transmission rate in said second one of said two or more different transmission modes.

2. The WLAN transmitter device of claim 1 wherein said WLAN transmitter device is adapted to apply different modulation types in different transmission modes.

3. The WLAN transmitter device of claim 2 wherein said modulation types include one or more of DSSS (Direct Sequence Spread Spectrum), FHSS (Frequency Hopping Spread Spectrum) and OFDM (Orthogonal Frequency Division Multiplexing) modulation types.

4. The WLAN transmitter device of claim 1 wherein said WLAN transmitter device is adapted to apply different modulation methods in different transmission modes.

5. The WLAN transmitter device of claim 4 wherein said modulation methods include one or more of BPSK (Binary Phase Shift Keying), QPSK (Quadrature Phase Shift Keying), CCK (Complementary Code Keying), and QAM (Quadrature Amplitude Modulation) modulation methods.

6. The WLAN transmitter device of claim 1 wherein said transmission gain controller is adapted to access a mode/gain table having stored therein transmission gain factors for each of said two or more different transmission modes.

7. The WLAN transmitter device of claim 1 wherein said transmission gain controller is adapted to determine a currently used transmission rate and access a rate/gain table having stored therein transmission gain factors for each transmission rate.

8. The WLAN transmitter device of claim 1 wherein said transmission gain controller is adapted to determine a currently used transmission rate and determine said transmission gain by applying a predefined transmission gain calculation algorithm to said currently used transmission rate.

9. The WLAN transmitter device of claim 1 wherein said data transmission section comprises an RF (Radio Frequency) transmission section and the WLAN transmitter device further comprises:

a baseband section connected to said RF transmission section, for performing baseband data processing, wherein said transmission gain controller is comprised in said baseband section.

10. The WLAN transmitter device of claim 9 wherein said baseband section comprises a baseband transmitter unit arranged for outputting digital data to be transmitted, said RF transmission section comprises a digital-to-analog converter for converting digital data to be transmitted to an analog signal, and said data transmission section further comprises a multiplier unit for multiplying the digital data output from said baseband transmitter unit with a factor corresponding to said transmission gain determined by said transmission gain controller, to provide digital data to be provided to said digital-to-analog converter.

11. The WLAN transmitter device of claim 10 wherein said multiplier unit is comprised in said baseband section.

12. The WLAN transmitter device of claim 10 wherein said multiplier unit is comprised in said data transmission section.

13. The WLAN transmitter device of claim 1 being IEEE 802.11 compliant.

14. An integrated circuit chip providing WLAN (Wireless Local Area Network) transmitter capabilities for transmitting data in two or more different transmission modes at different transmission rates, comprising:

a transmission gain control circuit for determining a transmission gain to be applied when transmitting data; and

a data transmission circuit for transmitting data at a transmission gain determined by said transmission gain control circuit,

wherein said transmission gain determined by said transmission gain control circuit is transmission mode dependent, with the transmission gain applied in a first one of said two or more different transmission modes being greater that the transmission gain applied in a second one of said two or more different transmission modes if the transmission rate in said first one of said two or more different transmission modes is smaller than the transmission rate in said second one of said two or more different transmission modes.

15. A WLAN (Wireless Local Area Network) transmission method of transmitting data in two or more different transmission modes at different transmission rates, the method comprising:

determining a transmission gain to be applied when transmitting data; and

transmitting data at a determined transmission gain,

wherein said determined transmission gain is transmission mode dependent, with the transmission gain applied in a first one of said two or more different transmission modes being greater that the transmission gain applied in a second one of said two or more different transmission modes if the transmission rate in said first one of said two or more different transmission modes is smaller than the transmission rate in said second one of said two or more different transmission modes.

16. The WLAN transmission method of claim 15 wherein different modulation types are applied in different transmission modes.

17. The WLAN transmission method of claim 16 wherein said modulation types include one or more of DSSS (Direct Sequence Spread Spectrum), FHSS (Frequency Hopping Spread Spectrum) and OFDM (Orthogonal Frequency Division Multiplexing) modulation types.

18. The WLAN transmission method of claim 15 wherein different modulation methods are applied in different transmission modes.

19. The WLAN transmission method of claim 18 wherein said modulation methods include one or more of BPSK (Binary Phase Shift Keying), QPSK (Quadrature Phase Shift Keying), CCK (Complementary Code Keying), and QAM (Quadrature Amplitude Modulation) modulation methods.

20. The WLAN transmission method of claim 15 wherein determining a transmission gain comprises:

accessing a mode/gain table having stored therein transmission gain factors for each of said two or more different transmission modes.

21. The WLAN transmission method of claim 15 wherein determining a transmission gain comprises:

determining a currently used transmission rate; and

accessing a rate/gain table having stored therein transmission gain factors for each transmission rate.

22. The WLAN transmission method of claim 15 wherein determining a transmission gain comprises:

determining a currently used transmission rate; and

applying a predefined transmission gain calculation algorithm to said currently used transmission rate.

23. The WLAN transmission method of claim 15 wherein the data transmission is performed by an RF (Radio Frequency) transmission section and the method further comprises:

performing baseband data processing in a baseband section connected to said RF transmission section,

wherein the transmission gain is determined by said baseband section.

24. The WLAN transmission method of claim 23 further comprising:

multiplying digital data output from said baseband section with a factor corresponding to said determined transmission gain to provide digital data to be provided to said RF transmission section.

25. The WLAN transmission method of claim 24 wherein the multiplication is performed by said baseband section.

26. The WLAN transmission method of claim 24 wherein the multiplication is performed by said RF transmission section.

27. The WLAN transmission method of claim 15 adapted to operate an IEEE 802.11 compliant WLAN transmitter device.