METHODS AND APPARATUS FOR INCREASING DIVERSITY IN DOWNLINK TRANSMISSIONS

• US 20140269768A1
• Filed: 03/14/2013
• Published: 09/18/2014
• Est. Priority Date: 03/14/2013
• Status: Abandoned Application

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Vermani, Sameer, Tian, Bin, va Zelst, Albert
• Application Number:
  US13/826,014
• Publication Number:
  US 20140269768A1
• Time in Patent Office: Days
• US Class Current: 370/474
• CPC Class Codes: H04B 7/0669 using different channel coding between antennas space-time coding H04L1/0618
• CPC Class Codes: H04B 7/0671 using different delays between antennas
• CPC Class Codes: H04B 7/068 using space frequency diversity space-frequency coding H04L1/0606
• CPC Class Codes: H04B 7/12 Frequency diversity
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers

Abstract

Certain aspects of the present disclosure provide methods and apparatus for obtaining second-order downlink spatial diversity within a wireless communication system in accordance with IEEE 802.11ah, for example. One example method generally includes generating a frame comprising a preamble having at least one field, replicating at least one bit of the at least one field to form a replica of the at least one bit, transmitting the at least one bit via a first antenna, and transmitting the replica of the at least one bit via a second antenna. Another example method generally includes generating at least two space-time streams; transmitting, via a first pair of antennas, the at least two space-time streams in a first frequency band; and transmitting, via a second pair of antennas, the at least two space-time streams in a second frequency band.

Claims

1. An apparatus for wireless communications, comprising:

a first antenna;

a second antenna;

a processing system configured to;

generate a frame comprising a preamble having at least one field; and

replicate at least one bit of the at least one field to form a replica of the at least one bit; and

a transmitter configured to;

transmit the at least one bit via the first antenna; and

transmit the replica of the at least one bit via the second antenna.

2. The apparatus of claim 1, wherein the transmitter is configured to transmit the frame in a channel having a bandwidth of about 1 MHz.

3. The apparatus of claim 1, wherein the transmitter is configured to transmit the at least one field using binary phase-shift keying (BPSK) and a coding rate of ½

.

4. The apparatus of claim 1, wherein the transmitter is configured to:

transmit, via the first antenna, the at least one bit at a first frequency; and

transmit, via the second antenna, the replica of the at least one bit at a second frequency.

5. The apparatus of claim 4, wherein the first frequency is above DC and wherein the second frequency is below DC.

6. The apparatus of claim 1, wherein the apparatus further comprises a third antenna and wherein the transmitter is configured to:

transmit, via the first antenna, a first bit of the at least one field at a first frequency;

transmit, via the second antenna, a replica of the first bit at the first frequency;

transmit, via the second antenna, a second bit of the at least one field at a second frequency; and

transmit, via the third antenna, a replica of the second bit at the second frequency.

7. The apparatus of claim 6, wherein the transmitter is further configured to:

transmit, via the third antenna, a third bit of the at least one field at a third frequency; and

transmit, via the first antenna, a replica of the third bit at the third frequency.

8. The apparatus of claim 1, wherein the at least one field comprises at least one of a signal (SIG) field or a short training field (STF).

9. A method for wireless communications, comprising:

generating a frame comprising a preamble having at least one field;

replicating at least one bit of the at least one field to form a replica of the at least one bit;

transmitting the at least one bit via a first antenna; and

transmitting the replica of the at least one bit via a second antenna.

10. The method of claim 9, wherein the frame is transmitted in a channel having a bandwidth of about 1 MHz.

11. The method of claim 9, wherein the at least one field is transmitted using binary phase-shift keying (BPSK) and a coding rate of ½

.

12. The method of claim 9, wherein transmitting the at least one bit comprises transmitting, via the first antenna, the at least one bit at a first frequency and wherein transmitting the replica of the at least one bit comprises transmitting, via the second antenna, the replica of the at least one bit at a second frequency.

13. The method of claim 12, wherein the first frequency is above DC and wherein the second frequency is below DC.

14. The method of claim 9, further comprising:

transmitting, via the first antenna, a first bit of the at least one field at a first frequency;

transmitting, via the second antenna, a replica of the first bit at the first frequency;

transmitting, via the second antenna, a second bit of the at least one field at a second frequency; and

transmitting, via a third antenna, a replica of the second bit at the second frequency.

15. The method of claim 14, further comprising:

transmitting, via the third antenna, a third bit of the at least one field at a third frequency; and

transmitting, via the first antenna, a replica of the third bit at the third frequency.

16. The method of claim 9, wherein the at least one field comprises at least one of a signal (SIG) field or a short training field (STF).

17. An apparatus for wireless communications, comprising:

means for generating a frame comprising a preamble having at least one field;

means for replicating at least one bit of the at least one field to form a replica of the at least one bit;

means for transmitting the at least one bit via a first antenna; and

means for transmitting the replica of the at least one bit via a second antenna.

18. The apparatus of claim 17, wherein the frame is transmitted in a channel having a bandwidth of about 1 MHz.

19. The apparatus of claim 17, wherein the at least one field is transmitted using binary phase-shift keying (BPSK) and a coding rate of ½

.

20. The apparatus of claim 17, wherein the means for transmitting the at least one bit is configured to transmit, via the first antenna, the at least one bit at a first frequency and wherein the means for transmitting the replica of the at least one bit is configured to transmit, via the second antenna, the replica of the at least one bit at a second frequency.

21. The apparatus of claim 20, wherein the first frequency is above DC and wherein the second frequency is below DC.

22. The apparatus of claim 17, further comprising:

means for transmitting, via the first antenna, a first bit of the at least one field at a first frequency;

means for transmitting, via the second antenna, a replica of the first bit at the first frequency;

means for transmitting, via the second antenna, a second bit of the at least one field at a second frequency; and

means for transmitting, via a third antenna, a replica of the second bit at the second frequency.

23. The apparatus of claim 22, further comprising:

means for transmitting, via the third antenna, a third bit of the at least one field at a third frequency; and

means for transmitting, via the first antenna, a replica of the third bit at the third frequency.

24. The apparatus of claim 17, wherein the at least one field comprises at least one of a signal (SIG) field or a short training field (STF).

25. A computer-program product for wireless communications, comprising a computer-readable medium having instructions executable to:

generate a frame comprising a preamble having at least one field;

replicate at least one bit of the at least one field to form a replica of the at least one bit;

transmit the at least one bit via a first antenna; and

transmit the replica of the at least one bit via a second antenna.

26. An apparatus for wireless communications, comprising:

a first antenna;

a second antenna;

a processing system configured to;

generate a frame comprising a preamble having at least one field; and

replicate at least one bit of the at least one field to form a replica of the at least one bit; and

a transmitter configured to;

transmit, via the first and second antennas, the at least one bit at a first frequency;

transmit, via the first antenna, the replica of the at least one bit at a second frequency; and

transmit, via the second antenna, a negative of the replica of the at least one bit at the second frequency.

27. The apparatus of claim 26, wherein the transmitter is configured to transmit the frame in a channel having a bandwidth of about 1 MHz.

28. The apparatus of claim 26, wherein the transmitter is configured to transmit the at least one field using binary phase-shift keying (BPSK) and a coding rate of ½

.

29. The apparatus of claim 26, wherein the first frequency is above DC and wherein the second frequency is below DC.

30. The apparatus of claim 26, wherein the at least one field comprises at least one of a signal (SIG) field or a short training field (STF).

31. A method for wireless communications, comprising:

generating a frame comprising a preamble having at least one field;

replicating at least one bit of the at least one field to form a replica of the at least one bit;

transmitting, via a first antenna and a second antenna, the at least one bit at a first frequency;

transmitting, via the first antenna, the replica of the at least one bit at a second frequency; and

transmitting, via the second antenna, a negative of the replica of the at least one bit at the second frequency.

32. The method of claim 31, wherein the frame is transmitted in a channel having a bandwidth of about 1 MHz.

33. The method of claim 31, wherein the at least one field is transmitted using binary phase-shift keying (BPSK) and a coding rate of ½

.

34. The method of claim 31, wherein the first frequency is above DC and wherein the second frequency is below DC.

35. The method of claim 31, wherein the at least one field comprises at least one of a signal (SIG) field or a short training field (STF).

36. An apparatus for wireless communications, comprising:

means for generating a frame comprising a preamble having at least one field;

means for replicating at least one bit of the at least one field to form a replica of the at least one bit;

means for transmitting, via a first antenna and a second antenna, the at least one bit at a first frequency;

means for transmitting, via the first antenna, the replica of the at least one bit at a second frequency; and

means for transmitting, via the second antenna, a negative of the replica of the at least one bit at the second frequency.

37. The apparatus of claim 36, wherein the frame is transmitted in a channel having a bandwidth of about 1 MHz.

38. The apparatus of claim 36, wherein the at least one field is transmitted using binary phase-shift keying (BPSK) and a coding rate of ½

.

39. The apparatus of claim 36, wherein the first frequency is above DC and wherein the second frequency is below DC.

40. The apparatus of claim 36, wherein the at least one field comprises at least one of a signal (SIG) field or a short training field (STF).

41. A computer-program product for wireless communications, comprising a computer-readable medium having instructions executable to:

generate a frame comprising a preamble having at least one field;

replicate at least one bit of the at least one field to form a replica of the at least one bit;

transmit, via a first antenna and a second antenna, the at least one bit at a first frequency;

transmit, via the first antenna, the replica of the at least one bit at a second frequency; and

transmit, via the second antenna, a negative of the replica of the at least one bit at the second frequency.

42. An apparatus for wireless communications, comprising:

a first pair of antennas;

a second pair of antennas;

a processing system configured to generate at least two space-time streams; and

a transmitter configured to;

transmit, via the first pair of antennas, the at least two space-time streams in a first frequency band; and

transmit, via the second pair of antennas, the at least two space-time streams in a second frequency band.

43. The apparatus of claim 42, further comprising a third pair of antennas, wherein the transmitter is further configured to transmit, via the third pair of antennas, the at least two space-time streams in a third frequency band.

44. The apparatus of claim 43, wherein the first pair of antennas comprises a first antenna and a second antenna, wherein the second pair of antennas comprises the second antenna and a third antenna, and wherein the third pair of antennas comprises the third antenna and the first antenna.

45. The apparatus of claim 42, wherein the first frequency band is above DC and wherein the second frequency band is below DC.

46. A method for wireless communications, comprising:

generating at least two space-time streams;

transmitting, via a first pair of antennas, the at least two space-time streams in a first frequency band; and

transmitting, via a second pair of antennas, the at least two space-time streams in a second frequency band.

47. The method of claim 46, further comprising transmitting, via a third pair of antennas, the at least two space-time streams in a third frequency band.

48. The method of claim 47, wherein the first pair of antennas comprises a first antenna and a second antenna, wherein the second pair of antennas comprises the second antenna and a third antenna, and wherein the third pair of antennas comprises the third antenna and the first antenna.

49. The method of claim 46, wherein the first frequency band is above DC and wherein the second frequency band is below DC.

50. An apparatus for wireless communications, comprising:

means for generating at least two space-time streams;

means for transmitting, via a first pair of antennas, the at least two space-time streams in a first frequency band; and

means for transmitting, via a second pair of antennas, the at least two space-time streams in a second frequency band.

51. The apparatus of claim 50, further comprising means for transmitting, via a third pair of antennas, the at least two space-time streams in a third frequency band.

52. The apparatus of claim 51, wherein the first pair of antennas comprises a first antenna and a second antenna, wherein the second pair of antennas comprises the second antenna and a third antenna, and wherein the third pair of antennas comprises the third antenna and the first antenna.

53. The apparatus of claim 50, wherein the first frequency band is above DC and wherein the second frequency band is below DC.

54. A computer-program product for wireless communications, comprising a computer-readable medium comprising instructions executable to:

generate at least two space-time streams;

transmit, via a first pair of antennas, the at least two space-time streams in a first frequency band; and

transmit, via a second pair of antennas, the at least two space-time streams in a second frequency band.

55. An access point, comprising:

a first pair of antennas;

a second pair of antennas;

a processing system configured to generate at least two space-time streams;

a transmitter configured to;

transmit, via the first pair of antennas, the at least two space-time streams in a first frequency band; and

transmit, via the second pair of antennas, the at least two space-time streams in a second frequency band; and

a memory component configured to store the at least two space-time streams before transmission.

56. An access point, comprising:

a first antenna;

a second antenna;

a processing system configured to;

generate a frame comprising a preamble having at least one field; and

replicate at least one bit of the at least one field to form a replica of the at least one bit;

a transmitter configured to;

transmit the at least one bit via the first antenna; and

transmit the replica of the at least one bit via the second antenna; and

a memory component configured to store the frame before transmission.

57. An access point, comprising:

a first antenna;

a second antenna;

a processing system configured to;

generate a frame comprising a preamble having at least one field; and

replicate at least one bit of the at least one field to form a replica of the at least one bit;

a transmitter configured to;

transmit, via the first and second antennas, the at least one bit at a first frequency;

transmit, via the first antenna, the replica of the at least one bit at a second frequency; and

transmit, via the second antenna, a negative of the replica of the at least one bit at the second frequency; and

a memory component configured to store the frame before transmission.