WLAN Device and Method Thereof

• US 20130107912A1
• Filed: 07/08/2011
• Published: 05/02/2013
• Est. Priority Date: 07/09/2010
• Status: Abandoned Application

• Current Assignee: MediaTek Singapore Pte. Ltd. (MediaTek, Inc.)
• Original Assignee: MediaTek Singapore Pte. Ltd. (MediaTek, Inc.)
• Inventors: Ponnampalam, Vishakan
• Application Number:
  US13/512,508
• Publication Number:
  US 20130107912A1
• Time in Patent Office: Days
• US Class Current: 375/147
• CPC Class Codes: H04B 1/707 using direct sequence modulation
• CPC Class Codes: H04L 27/0008 arrangements for allowing a transmitter or receiver to use more than one type of modulation negotiating modulation type for two-way transmission paths H04L5/1453
• CPC Class Codes: H04L 27/20 Modulator circuits; Transmitter circuits
• CPC Class Codes: H04L 27/2603 Signal structure ensuring backward compatibility with legacy system
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 27/2626 Arrangements specific to the transmitter only
• CPC Class Codes: H04L 27/36 Modulator circuits; Transmitter circuits

Abstract

A Wireless Local Area Network (WLAN) device and a method thereof. The Wireless Local Area Network (WLAN) device generates a Physical Layer (PHY) protocol data unit (PPDU) comprising a preamble field, a header field and a payload field for transmission, and comprises a MAC module, a modulator, and an RF module. The MAC module generates a header data sequence comprising bandwidth information of the transmission. The modulator modulates the header data sequence using S-QPSK modulation to generate the header field of the PPDU. The RF module transmits the header field.

Claims

1. A Wireless Local Area Network (WLAN) device, generating a Physical Layer (PHY) protocol data unit (PPDU) comprising a preamble field, a header field and a payload field for transmission, comprising:

a MAC module, generating a header data sequence comprising bandwidth information of the transmission;

a modulator, modulating the header data sequence using spread QPSK (S-QPSK) modulation to generate the header field of the PPDU; and

an RF module, transmitting the header field.

2. The WLAN device of claim 1, wherein the modulator splits the header data sequence in two parts, and modulates the two parts using the S-QPSK modulation to generate two OFDM symbols.

3. The WLAN device of claim 1, wherein the modulator splits the header data sequence to generate a first part and a second part, and modulates the first part using BPSK modulation to generate a first OFDM symbol of the header field and the second part using the S-QPSK modulation to generate the second OFDM symbol of the header field.

4. The WLAN device of claim 1, wherein the modulator modulates the header data sequence using the spread QPSK modulation to generate an OFDM symbol comprising first and second sub-symbols, each is transmitted on a separate sub-carrier.

5. The WLAN device of claim 4, wherein the RF module transmits the first and second sub-symbols on the two sub-carriers separated by a constant frequency offset.

6. The WLAN device of claim 4, wherein the second sub-symbol is a conjugate of the first sub-symbol.

7. The WLAN device of claim 1, further comprising an encoder, encoding the header data sequence in a single Forward Error Correction (FEC) code block.

8. The WLAN device of claim 1, further comprising an encoder, encoding the header data sequence in a convolutional code block.

9. A WLAN device, receiving data transmission of a Physical Layer (PHY) protocol data unit (PPDU) comprising a preamble field, a header field and a payload field, comprising:

an RF module, receiving the PPDU comprising the header field, wherein the header field comprises bandwidth information of the data transmission; and

a symbol detector, determining whether the header field is S-QPSK modulated, and determining the PPDU conforms to a WLAN communication protocol when the header field is S-QPSK modulated.

10. The WLAN device of claim 9, wherein the header field comprises two OFDM symbols, and the symbol detector determines the PPDU conforms to the WLAN communication protocol when the two OFDM symbols are S-QPSK modulated.

11. The WLAN device of claim 9, wherein the header field comprises two OFDM symbols, and the symbol detector determines the PPDU conforms to the WLAN communication protocol when one OFDM symbol in the header field is BPSK modulated, and the other OFDM symbol in the header field is S-QPSK modulated.

12. The WLAN device of claim 9, wherein the header field comprises two OFDM symbols, and the symbol detector determines the PPDU conforms to the WLAN communication protocol when detecting one OFDM symbol in the header field is BPSK modulated, and the other OFDM symbol in the header field is in absence of the BPSK modulation.

13. The WLAN device of claim 9, wherein the header field comprises an OFDM symbol having two sub-symbols, and the RF modules receives the two sub-symbols on two separate sub-carriers.

14. The WLAN device of claim 12, wherein the RF module receives the two sub-symbols on the two sub-carriers separated by a constant frequency offset.

15. The WLAN device of claim 12, wherein one of the two sub-symbols is a conjugate of the other sub-symbol.

16. The WLAN device of claim 9, further comprising a decoder, decoding the header field using Forward Error Correction (FEC).

17. The WLAN device of claim 9, further comprising a decoder, decoding the header data sequence using Viterbi decoding.

18. A method, generating a Physical Layer (PHY) protocol data unit (PPDU) comprising a preamble field, a header field and a payload field for transmission by a WLAN device, comprising:

a MAC module generating a header data sequence comprising bandwidth information of the transmission;

a modulator modulating the header data sequence using S-QPSK modulation to generate the header field of the PPDU; and

an RF module transmitting the header field.

19. The method of claim 18, further comprising the modulator splitting the header data sequence in two parts, and wherein the modulating step comprises the modulator modulating the two parts using the S-QPSK modulation to generate two OFDM symbols.

20. The method of claim 18, further comprising the modulator splitting the header data sequence to generate a first part and a second part, and wherein the modulating step comprises the modulator modulating the first part using BPSK modulation to generate to generate a first OFDM symbol of the header field and the second part using the S-QPSK modulation to generate the second OFDM symbol of the header field.

21. The method of claim 18, wherein the modulating step comprises the modulator modulating the header data sequence using the S-QPSK modulation to generate an OFDM symbol comprising first and second sub-symbols, each is transmitted on a separate sub-carrier.

22. The method of claim 21, wherein the transmitting step comprises the RF module transmitting the first and second sub-symbols on the two sub-carriers separated by a constant frequency offset.

23. The method of claim 21, wherein the second sub-symbol is a conjugate of the first sub-symbol.

24. The Method of claim 18, further comprising an encoder encoding the header data sequence in a single Forward Error Correction (FEC) code block.

25. The method of claim 18, further comprising an encoder encoding the header data sequence in a convolutional code block.

26. A method, receiving data transmission of a Physical Layer (PHY) protocol data unit (PPDU) comprising a preamble field, a header field and a payload field by a WLAN device, comprising:

an RF module receiving the PPDU comprising the header field, wherein the header field comprises bandwidth information of the data transmission;

a symbol detector determining whether the header field is S-QPSK modulated; and

the symbol detector determining the PPDU conforms to a WLAN communication protocol when the header field is S-QPSK modulated.

27. The method of claim 26, wherein the header field comprises two OFDM symbols, and the determining the PPDU conforms to the WLAN communication protocol step comprises the symbol detector determining the PPDU conforms to the WLAN communication protocol when the two OFDM symbols are S-QPSK modulated.

28. The method of claim 26, wherein the header field comprises two OFDM symbols, and the determining the PPDU conforms to the WLAN communication protocol step comprises the symbol detector determining the PPDU conforms to the WLAN communication protocol when one OFDM symbol in the header field is S-QPSK modulated, and the other OFDM symbol in the header field is BPSK modulated.

29. The method of claim 26, wherein the header field comprises two OFDM symbols, and the determining the PPDU conforms to the WLAN communication protocol step comprises the symbol detector determining the PPDU conforms to the WLAN communication protocol when detecting one OFDM symbol in the header field is BPSK modulated, and the other OFDM symbol in the header field is in absence of the BPSK modulation.

30. The method of claim 26, wherein the header field comprises an OFDM symbol having two sub-symbols, and the receiving step comprises the RF modules receiving the two sub-symbols on two separate sub-carriers.

31. The method of claim 30, wherein the receiving step comprises the RF module receiving the two sub-symbols on the two sub-carriers separated by a constant frequency offset.

32. The method of claim 30, wherein one of the two sub-symbols is a conjugate of the other sub-symbol.

33. The method of claim 26, further comprising a decoder decoding the header field using Forward Error Correction (FEC).

34. The method of claim 26, further comprising a decoder decoding the header data sequence using Viterbi decoding.