Increasing capacity in wireless communications

• US 9,014,152 B2
• Filed: 04/15/2009
• Issued: 04/21/2015
• Est. Priority Date: 06/09/2008
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Jou, Yu-Cheun, Black, Peter J., Attar, Rashid Ahmed A.
• Primary Examiner(s): Ferris, Derrick
• Assistant Examiner(s): Acolatse, Kodzovi
• Application Number:
  US12/424,050
• Publication Number:
  US 20090303968A1
• Time in Patent Office: 2,197 Days
• Field of Search: 370/458
• US Class Current: 370/336
• CPC Class Codes: H04B 2201/709709 Methods of preventing interference
• CPC Class Codes: H04L 1/0002 by adapting the transmission rate
• CPC Class Codes: H04L 1/0025 Transmission of mode-switching indication
• CPC Class Codes: H04L 1/0027 Scheduling of signalling, e.g. occurrence thereof
• CPC Class Codes: H04L 1/0029 Reduction of the amount of signalling, e.g. retention of useful signalling or differential signalling power control H04W52/04
• CPC Class Codes: H04L 1/0045 Arrangements at the receiver end
• CPC Class Codes: H04L 1/1607 Details of the supervisory signal
• CPC Class Codes: H04L 1/1854 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 2001/0092 Error control systems characterised by the topology of the transmission link
• CPC Class Codes: H04W 52/44 in connection with interruption of transmission
• CPC Class Codes: H04W 52/58 Format of the TPC bits

Abstract

Techniques to increase capacity in a wireless communications system. Systematic non-transmission, or “blanking,” of minimal-rate frames transmitted in a communications system is provided. In an exemplary embodiment, eighth rate frames in a cdma2000 voice communications system are systematically substituted with null-rate frames carrying zero traffic bits. The receiver detects the presence of null rate or non-null rate transmissions and processes the received frames accordingly. Techniques for changing the pilot transmission gating pattern to assist the receiver in detecting null rate frames are provided. In another aspect, early termination of a signal transmission over a wireless communications link is provided. In an exemplary embodiment, a base station (BS) transmits power control groups (PCG'"'"'s) for a frame over a forward link (FL) to a mobile station (MS) until accurate reception of the frame is acknowledged by the MS over a reverse link (RL), possibly before all PCG'"'"'s of the frame are received.

Claims

1. A method for early termination of sequential frame transmissions over a communications channel, the method comprising:

commencing transmission of a first frame to a receiver, each frame formatted into a plurality of sequential sub-segments and sequentially transmitted without awaiting sub-segment acknowledgment until a successful decode of the first frame;

receiving an acknowledgment message from the receiver during the transmission of the first frame, the acknowledgment message transmitted at one of predetermined times designated by an acknowledgement mask designating an interval having a duration of less than a complete one of the plurality of sequential sub-segments and indicating a successful decode of the first frame based on an already transmitted portion of the plurality of sequential sub-segments of the first frame; and

ceasing the transmission of an untransmitted portion of the plurality of sequential sub-segments of the first frame after receiving the acknowledgment message.

2. The method of claim 1, each frame allotted a fixed time interval for transmission, further comprising:

commencing transmission of a second frame after the fixed time interval has elapsed for the first frame, the second frame immediately following the first frame in frame sequence.

3. The method of claim 1, further comprising adjusting a transmit power of the first frame in response to receiving a power control message from the receiver.

4. The method of claim 1, the commencing transmission comprising:

continuously transmitting sub-segments of the first frame in sequence to the receiver.

5. The method of claim 1, each frame comprising fractionally encoded bits interleaved over time.

6. A method for early termination of sequential frame transmissions over a communications channel, the method comprising:

commencing reception of a first frame from a transmitter, each frame formatted into a plurality of sequential sub-segments and sequentially received without awaiting sub-segment acknowledgment until a successful decode of the first frame;

attempting to decode the first frame prior to receiving the entire first frame;

determining a successful frame decode based on a result of the attempting; and

transmitting an acknowledgment message to the transmitter based on determining the successful frame decode, the acknowledgment message transmitted at one of predetermined times designated by an acknowledgement mask designating an interval having a duration of less than a complete one of the plurality of sequential sub-segments and indicating a successful decode of the first frame based on an already transmitted portion of the plurality of sequential sub-segments of the first frame, wherein the acknowledgment message causes the transmitter to cease transmission of an untransmitted portion of the plurality of sequential sub-segments of the first frame.

7. The method of claim 6, each frame allotted a fixed time interval for transmission, further comprising:

commencing reception a second frame after the fixed time interval has elapsed for the first frame, the second frame immediately following the first frame in frame sequence.

8. The method of claim 6, further comprising transmitting a power control message to the transmitter to adjust a transmit power of the first frame.

9. The method of claim 6, the commencing reception comprising:

continuously receiving sub-segments of the first frame in sequence from the transmitter.

10. The method of claim 6, wherein transmitting the acknowledgment message further comprises transmitting only at the one of the predetermined times.

11. The method of claim 6, further comprising receiving the acknowledgment mask from the transmitter.

12. The method of claim 6, the transmitting an acknowledgment message comprising:

applying a non-zero gain to an acknowledgment signal comprising a Walsh function associated with the acknowledgment message; and

combining the acknowledgment signal with a traffic signal for transmission.

13. The method of claim 6, the commencing reception of the first frame being received on a first channel, the transmitting the acknowledgment message being done on a first acknowledgment channel, the method further comprising:

commencing reception of a second frame on a second channel from the transmitter;

attempting to decode the second frame prior to receiving the entire second frame;

determining a successful frame decode based on a result of the attempting to decode the second frame; and

transmitting an acknowledgment message to the transmitter based on determining the successful frame decode for the second frame, wherein the acknowledgment message is operable to cease transmission of the second frame.

14. The method of claim 6, further comprising:

commencing reception of a second frame from a second transmitter;

attempting to decode the second frame prior to receiving the entire second frame;

determining a successful decode of the second frame based on a result of the attempting;

transmitting an acknowledgment message to the second transmitter based on determining the successful decode of the second frame, wherein the acknowledgment message is operable to terminate transmission of an untransmitted portion of the plurality of sequential sub-segments of the second frame, the transmitting the acknowledgment message to the transmitter comprising modulating at least one bit on a common acknowledgment channel, the transmitting the acknowledgment message to the second transmitter comprising modulating at least one other bit on the same common acknowledgment channel.

15. The method of claim 14, further comprising spreading the common acknowledgment channel using a single Walsh function.

16. The method of claim 14, the at least one bit corresponding to the acknowledgment message transmitted to the transmitter being time multiplexed on the same common acknowledgment channel with the at least one other bit corresponding to the acknowledgment message transmitted to the second transmitter.

17. The method of claim 6, the transmitting an acknowledgment message comprising modulating a signal on a distinct Walsh code using on-off keying.

18. The method of claim 6, the transmitting an acknowledgment message comprising modulating at least one ACK bit of a traffic channel, the at least one ACK bit supplanting at least one traffic bit on the traffic channel.

19. The method of claim 18, the position of the ACK bit in the traffic channel varied on a per-frame basis.

20. An apparatus for early termination of sequential frame transmissions over a communications channel, the apparatus comprising:

a transmitter configured to commence transmission of a first frame to a receiver, each frame formatted into a plurality of sequential sub-segments and sequentially transmitted without awaiting sub-segment acknowledgment until a successful decode of the first frame;

a receiver module configured to receive an acknowledgment message from the receiver during the transmission of the first frame, the acknowledgment message transmitted at one of predetermined times designated by an acknowledgement mask designating an interval having a duration of less than a complete one of the plurality of sequential sub-segments and indicating a successful decode of the first frame based on an already transmitted portion of the plurality of sequential sub-segments of the first frame; and

the transmitter configured to cease the transmission of an untransmitted portion of the plurality of sequential sub-segments of the first frame after receiving the acknowledgment message.

21. The apparatus of claim 20, each frame allotted a fixed time interval for transmission, the transmitter further configured to commence transmission of a second frame after the fixed time interval has elapsed for the first frame, the second frame immediately following the first frame in frame sequence.

22. The apparatus of claim 20, the transmitter further configured to adjust a transmit power of the first frame in response to receiving a power control message from the receiver.

23. The apparatus of claim 20, each frame formatted into a plurality of sequential sub-segments, the transmitter configured to continuously transmit by:

continuously transmitting sub-segments of the first frame in sequence to the receiver.

24. The apparatus of claim 20, each frame comprising fractionally encoded bits interleaved over time.

25. An apparatus for early termination of sequential frame transmissions over a communications channel, the apparatus comprising:

a receiver configured to commence reception of a first frame from a transmitter, each frame formatted into a plurality of sequential sub-segments and sequentially received without awaiting sub-segment acknowledgment until a successful decode of the first frame;

a processor configured to;

attempt to decode the first frame prior to receiving the entire first frame;

determine a successful frame decode based on a result of the attempting; and

a transmitter module configured to transmit an acknowledgment message to the transmitter based on determining the successful frame decode, the acknowledgment message transmitted at one of predetermined times designated by an acknowledgement mask designating an interval having a duration of less than a complete one of the plurality of sequential sub-segments and indicating a successful decode of the first frame based on an already transmitted portion of the plurality of sequential sub-segments of the first frame, wherein the acknowledgment message causes the transmitter to cease the transmission of an untransmitted portion of the plurality of sequential sub-segments of the first frame.

26. The apparatus of claim 25, each frame allotted a fixed time interval for transmission, the processor further configured to:

commence receiving a second frame after the fixed time interval has elapsed for the first frame, the second frame immediately following the first frame in frame sequence.

27. The apparatus of claim 25, the transmitter module further configured to transmit a power control message to the transmitter to adjust a transmit power of the first frame.

28. The apparatus of claim 25, the receiver configured to commence reception by:

continuously receiving sub-segments of the first frame in sequence from the transmitter.

29. The apparatus of claim 28, the transmitter module further configured to transmit the acknowledgment message only at the one of the predetermined times.

30. The apparatus of claim 25, the receiver further configured to receive the acknowledgment mask from the transmitter.

31. The apparatus of claim 25, the transmitter module configured to transmit the acknowledgment message by:

applying a non-zero gain to an acknowledgment signal comprising a Walsh function associated with the acknowledgment message; and

combining the acknowledgment signal with a traffic signal for transmission.

32. The apparatus of claim 25, the commencing reception of the frame being received on a first channel, the transmitter module further configured to transmit the acknowledgment message on a first acknowledgment channel, the receiver further configured to commence reception of a second frame on a second channel from the transmitter;

the processor further configured to attempt to decode the second frame prior to receiving the entire second frame, the processor further configured to determine a successful frame decode based on a result of the attempting to decode the second frame; and

the transmitter module further configured to transmit an acknowledgment message to the transmitter based on determining the successful frame decode for the second frame, wherein the acknowledgment message causes the transmitter to cease transmission of the second frame.

33. The apparatus of claim 25, the receiver further configured to commence reception from a second transmitter of a second frame;

the processor further configured to attempt to decode the second frame prior to receiving the entire second frame;

the processor further configured to determine a successful decode of the second frame based on a result of the attempting;

the transmitter module further configured to transmit an acknowledgment message to the second transmitter based on determining the successful decode of the second frame, wherein the acknowledgment message causes the transmitter to terminate transmission of an untransmitted portion of the plurality of sequential sub-segments of the second frame, the transmitter module further configured to transmit the acknowledgment message to the transmitter by modulating at least one bit on a common acknowledgment channel, the transmitter module further configured to transmit the acknowledgment message to the second transmitter by modulating at least one other bit on the same common acknowledgment channel.

34. The apparatus of claim 33, the transmitter module further configured to spread the common acknowledgment channel using a single Walsh function.

35. The apparatus of claim 33, the at least one bit corresponding to the acknowledgment message transmitted to the transmitter being time multiplexed on the same common acknowledgment channel with the at least one other bit corresponding to the acknowledgment message transmitted to the second transmitter.

36. The apparatus of claim 25, the transmitter module further configured to transmit an acknowledgment message by modulating a signal on a distinct Walsh code using on-off keying.

37. The apparatus of claim 25, the transmitter module further configured to transmit an acknowledgment message by modulating at least one ACK bit of a traffic channel, the at least one ACK bit supplanting at least one traffic bit on the traffic channel.

38. The apparatus of claim 37, the position of the ACK bit in the traffic channel varied on a per-frame basis.

39. An apparatus for early termination of frame transmissions over a communications channel, the apparatus comprising:

means for commencing reception of a first frame from a transmitter, each frame formatted into a plurality of sequential sub-segments and sequentially received without awaiting sub-segment acknowledgment until a successful decode of the first frame;

means for terminating transmissions of an untransmitted portion of the plurality of sequential sub-segments from the transmitter prior to receiving the entire frame by transmitting an acknowledgment message to the transmitter based on determining the successful frame decode, the acknowledgment message transmitted at one of predetermined times designated by an acknowledgement mask designating an interval having a duration of less than a complete one of the plurality of sequential sub-segments and indicating a successful decode of the first frame based on an already transmitted portion of the plurality of sequential sub-segments of the first frame.

40. An apparatus for early termination of frame transmissions over a communications channel, the apparatus comprising:

means for commencing transmission of a first frame, each frame formatted into a plurality of sequential sub-segments and sequentially transmitted without awaiting sub-segment acknowledgment until a successful decode of the first frame;

means for terminating the transmission of an untransmitted portion of the plurality of sequential sub-segments receiving an acknowledgment message from the receiver during the transmission of the first frame, the acknowledgment message transmitted at one of predetermined times designated by an acknowledgement mask designating an interval having a duration of less than a complete one of the plurality of sequential sub-segments and indicating a successful decode of the first frame based on an already transmitted portion of the plurality of sequential sub-segments of the first frame based on a successful decode of the at least one transmitted sub-segment by a receiver.

41. A non-transitory computer-readable storage medium storing instructions for causing a computer to perform early termination of frame transmissions over a communications channel, the medium storing instructions for causing a computer to:

receive from a transmitter a first frame, each frame formatted into a plurality of sequential sub-segments and sequentially received without awaiting sub-segment acknowledgment until a successful decode of the first frame;

attempt to decode the frame prior to receiving the entire frame;

determine a successful frame decode based on a result of the attempting; and

transmit an acknowledgment message to the transmitter based on determining the successful frame decode, the acknowledgment message transmitted at one of predetermined times designated by an acknowledgement mask designating an interval having a duration of less than a complete one of the plurality of sequential sub-segments and indicating a successful decode of the first frame based on an already transmitted portion of the plurality of sequential sub-segments of the first frame, wherein the acknowledgment message is operable to terminate transmission of an untransmitted portion of the plurality of sequential sub-segments of the frame.

42. A non-transitory computer-readable storage medium storing instructions for causing a computer to perform for early termination of frame transmissions over a communications channel, each frame being allotted a fixed time interval for transmission, the medium storing instructions for causing a computer to:

commence transmission of a first frame, each frame formatted into a plurality of sequential sub-segments and sequentially transmitted without awaiting sub-segment acknowledgment until a successful decode of the first frame;

receive an acknowledgment message from a receiver during the transmitting the first frame, the acknowledgment message transmitted at one of predetermined times designated by an acknowledgement mask designating an interval having a duration of less than a complete one of the plurality of sequential sub-segments and indicating a successful decode of the first frame based on an already transmitted portion of the plurality of sequential sub-segments of the first frame;

cease transmission of an untransmitted portion of the plurality of sequential sub-segments of the first frame after receiving the acknowledgment message; and

start to transmit a second frame after the fixed time interval has elapsed for the first frame.

43. A method for early termination of sequential frame transmissions over a communications channel, the method comprising:

commencing transmission of a first frame to at least one receiver, each frame formatted into a plurality of sequential sub-segments and sequentially transmitted without awaiting sub-segment acknowledgment until a successful decode of the first frame;

receiving at least one acknowledgment message from the at least one receiver during the transmitting the first frame, the acknowledgment message transmitted at one of predetermined times designated by an acknowledgement mask designating an interval having a duration of less than a complete one of the plurality of sequential sub-segments and indicating a successful decode of the first frame based on an already transmitted portion of the plurality of sequential sub-segments of the first frame; and

ceasing transmission of an untransmitted portion of the plurality of sequential sub-segments of the first frame after receiving the first of the at least one acknowledgment message.

44. The method of claim 43, the at least one receiver comprising a first receiver and a second receiver, the receiving the at least one acknowledgment message from the at least one receiver comprising receiving an acknowledgment message from the first receiver and an acknowledgment message from the second receiver.

45. A method for early termination of sequential frame transmissions over a communications channel, the method comprising:

commencing reception of a first frame from at least one transmitter, each frame formatted into a plurality of sequential sub-segments and sequentially received without awaiting sub-segment acknowledgment until a successful decode of the first frame;

attempting to decode the first frame prior to receiving the entire first frame;

determining a successful frame decode based on a result of the attempting; and

transmitting an acknowledgment message based on determining the successful frame decode, the acknowledgment message transmitted at one of predetermined times designated by an acknowledgement mask designating an interval having a duration of less than a complete one of the plurality of sequential sub-segments and indicating a successful decode of the first frame based on an already transmitted portion of the plurality of sequential sub-segments of the first frame, wherein the acknowledgment message causes each of the at least one transmitter to cease transmission of an untransmitted portion of the plurality of sequential sub-segments of the first frame by each of the at least one transmitter.

46. The method of claim 45, the at least one transmitter comprising a first transmitter and a second transmitter, the transmitting the acknowledgment message comprising transmitting the acknowledgment message to both the first transmitter and the second transmitter.