Transmitting station for wireless telephone system with diversity transmission and method

• US 7,463,608 B2
• Filed: 03/12/2002
• Issued: 12/09/2008
• Est. Priority Date: 09/06/1994
• Status: Expired due to Fees

• Current Assignee: Intel Corporation
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Bolgiano, D. Ridgely, LaVean, Gilbert E
• Primary Examiner(s): Duong; Frank
• Application Number:
  US10/096,180
• Publication Number:
  US 20020105962A1
• Time in Patent Office: 2,464 Days
• Field of Search: 370/320, 370/321, 370328-339, 370/342, 370343-347, 370/441, 370/442, 375/130, 375141-147, 375/267, 375/299, 375/347, 455101-103, 455/500
• US Class Current: 370/335
• CPC Class Codes: G01S 5/10 Position of receiver fixed by co-ordinating a plurality of position lines defined by path-difference measurements , e.g. omega or decca systemsG01S5/12 takes precedence ; beacons and receivers cooperating therewith G01S1/306, G01S1/308
• CPC Class Codes: G01S 5/14 Determining absolute distances from a plurality of spaced points of known location
• CPC Class Codes: H01Q 21/29 Combinations of different interacting antenna units for giving a desired directional characteristic H01Q25/00 takes precedence
• CPC Class Codes: H04B 7/022 Site diversity; Macro-diversity using two or more spaced independent antennas H04B7/04
• CPC Class Codes: H04B 7/0671 using different delays between antennas
• CPC Class Codes: H04B 7/082 selecting best antenna path
• CPC Class Codes: H04B 7/0857 using maximum ratio combining techniques, e.g. signal-to- interference ratio [SIR], received signal strenght indication [RSS]
• CPC Class Codes: H04B 7/0888 with selection
• CPC Class Codes: H04W 56/00 Synchronisation arrangements
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

A transmitting station for communicating data in a cellular system utilizes transmission diversity by transmitting a plurality of signals. A transmitter is configured to transmit at least a first data signal corresponding to the data in a first time slot and to transmit a second data signal corresponding to the data in a second time slot. The second time slot occurs after the first time slot so that the first and second transmitted data signals are not simultaneously transmitted. Preferably, the transmitter includes a first antenna from which the first data signal is transmitted and a second antenna spaced apart from the first antenna from which the second data signal is transmitted. Where the transmitting station is for a CDMA system, the transmitter is configured to transmit said data signals as PN spread spectrum signals. In such case, an encoder is provided for spreading and modulating the data with PN codes to form the data signals. Preferably, different PN codes are used to form the data signals. In one embodiment, the PN codes are part of a PN code sequence produced by a PN code generator without resetting. The transmitting station may be a combined base station and transfer station.

Claims

1. In a wireless terrestrial code division multiple access (CDMA) communication system, wherein a synchronization code is communicated from a transmitting station to a subscriber station in a predetermined time frame format comprising a plurality of sequential time slots per time frame, a method at the transmitting station comprising:

transmitting a first signal corresponding to the synchronization code in a synchronization channel in a first time slot of the predetermined time frame format from a first antenna; and

transmitting a second signal corresponding to the synchronization code in the synchronization channel in a second time slot of the predetermined time frame format from a second antenna spaced apart from the first antenna, the second time slot occurring after the first time slot relative to the predetermined time frame format.

2. The method for a CDMA system transmitting station in accordance with claim 1, wherein the synchronization code is combined with a first sequence prior to transmission of the first signal and the synchronization code is combined with a second sequence prior to transmission of the second signal.

3. In a wireless terrestrial code division multiple access (CDMA) communication system, wherein a synchronization code is sent from a transmitting station to a subscriber station in a predetermined time frame format comprising a plurality of sequential time slots per time frame, a method at said transmitting station comprising:

transmitting a first signal corresponding to the synchronization code in a synchronization channel in a first time slot of the predetermined time frame format from a first antenna; and

transmitting a second signal corresponding to the synchronization code in the synchronization channel in a second time slot of the predetermined time frame format from a second antenna spaced apart from the first antenna, the second time slot occurring after the first time slot relative to the predetermined time frame format.

4. In a wireless terrestrial code division multiple access (CDMA) communication system, wherein control data is communicated from a transmitting station to a plurality of subscriber stations in a common control channel, a method comprising:

transmitting a first control data signal having first data over the common control channel from a first antenna from the transmitting station; and

transmitting a second control data signal having the first data processed and sent over the common control channel from a second antenna from the transmitting station spatially diverse from the first antenna;

wherein at least one symbol of the first data is transmitted as an at least one corresponding symbol at a different time on the second antenna;

wherein a spreading sequence for spreading the at least one symbol transmitted on the first antenna is continued for spreading the corresponding at least one symbol on the second antenna.

5. The method in accordance with claim 4, wherein one of the plurality subscriber stations receives the common control channel such that corresponding symbols of the first and second signals are combined.

6. The method in accordance with claim 5, wherein the one subscriber station receives a page over the common control channel.

7. The method in accordance with claim 4, wherein the common control channel has a plurality of time slots in a time frame and the transmitting station not transmitting any signals in at least one time slot of the time frame.

8. The method in accordance with claim 7, wherein one of the plurality of subscriber stations takes measurements during the at least one time slot where said transmitting station does not transmit any signals.

9. The method in accordance with claim 8, wherein the measurements include measurements of CDMA signals for use in facilitating a time difference of arrival calculation.

10. The method in accordance with claim 9, wherein one of the plurality of subscriber stations sends information related to time difference of arrival facilitating measurements to the transmitting station, the transmitting station determining a location of the subscriber station based on the sent information.

11. A code division multiple access (CDMA) transmitting station for communicating data in a terrestrial cellular system that utilizes transmission diversity comprising a transmitter configured to transmit a first data sequence over a common control channel on a first antenna and to transmit a second data sequence over the common control channel on a second antenna, the second data sequence having the first data sequence processed;

wherein at least one symbol of the first data is transmitted as an at least one corresponding symbol at a different time on the second antenna;

wherein a spreading sequence for the at least one symbol transmitted on the first antenna is continued for the spreading the corresponding at least one symbol on the second antenna;

wherein the second antenna spaced apart from the first antenna.

13. The transmitting station for a CDMA system in accordance with claim 11 wherein the common control channel has a plurality of time slots in a time frame and the transmitter is configured to not transmit any signals in at least one time slot of the time frame.

19. The transmitting station in accordance with claim 11 wherein the common control channel has a plurality of time slots in a time frame and the transmitter does not transmit any signals in at least one time slot of the time frame and the transmitting station includes a receiver to receive measurements of CDMA signals from a subscriber station to facilitate a time difference of arrival determination and includes a controller to determine a location of the subscriber station using the received measurements.

20. The transmitting station in accordance with claim 19 wherein the transmitter is configured to transmit location information of the determined location of the subscriber station to the subscriber station.

21. The transmitting station in accordance with claim 11 further comprising a receiver configured to receive measurements of CDMA signals to facilitate a time difference of arrival information determination and global positioning system information from a subscriber station.

12. A code division multiple access (CDMA) transmitting station for communicating a synchronization code in a predetermined time frame format comprising a plurality of sequential time slots per time frame in a terrestrial cellular system that utilizes transmission diversity comprising a transmitter configured to transmit a first signal corresponding to the synchronization code in a first time slot of the predetermined time frame format in a synchronization channel and to transmit a second signal corresponding to the synchronization code in a second time skt of the predetermined time frame format in the synchronization channel, the second time slot occurring after the first time slot relative to the time frame format wherein the transmitter indudes a first antenna from which the first signal is transmitted and a second antenna spaced apart from the first antenna from which the second signal is transmitted.

14. A transmitting station for communicating data in a cellular system that utilizes transmission diversity comprising a transmitter configured to transmit a first control data signal having first data over a common control channel and to transmit a second control data signal having the first data processed and sent over the common control channel from a second antenna spatially diverse from the first antenna and at least one symbol transmitted on the first antenna is transmitted as an at least one corresponding symbol at a different time on the second antenna;

wherein a spreading sequence for spreading the at least one symbol transmitted on the first antenna continues for spreading the corresponding at least one symbol on the second antenna.

15. The transmitting station in accordance with claim 14 wherein the first and second data have pages for subscriber stations.

16. The transmitting station in accordance with claim 14, further comprising a receiver to receive encrypted position information from a subscriber station.

17. The transmitting station in accordance with claim 16, wherein the common control channel has a plurality of time slots in the time frame and the transmitting station does not transmit any signals in at least one time slot of the time frame.

18. The transmitting station in accordance with claim 17 further comprising a receiver configured to receive measurements to facilitate a time difference of arrival determination and global positioning system information from a subscriber station.

22. A code division multiple access (CDMA) subscriber station, the CDMA subscriber station comprising:

a receiver configured to receive a first signal during a first one of a plurality of time slots and a second signal during a second one of the plurality of time slots, the first signal carrying a first sequence including a bit sequence combined with a first code sequence, and the second signal carrying synchronization information and a second sequence, the second sequence including the bit sequence combined with a second code sequence,

wherein the plurality of time slots are included in a frame, the first and second signals being transmitted by respective first and second ones of a plurality of antennas, the plurality of antennas being associated with a transmitting station, and the receiver is configured to diversity combine diversity transmitted data of a CDMA control channel by utilizing first information derived from the first and second signals; and

a controller configured to derive second information associated with the transmitting station, the synchronization information and the CDMA control channel being transmitted by the plurality of antennas of the transmitting station.

23. The CDMA subscriber station of claim 22, wherein the first code sequence is identical to the second code sequence.

24. The CDMA subscriber station of claim 22, wherein the first and second code sequences are different from one another.

25. The CDMA subscriber station of claim 22, wherein the receiver is configured to detect the bit sequence.

26. The CDMA subscriber station of claim 25, wherein the receiver selects the detected bit sequence associated with either the first one of the plurality time slots or the second one of the plurality of time slots.

27. The CDMA subscriber station of claim 25, wherein the bit sequence corresponds to the synchronization code.

28. The CDMA subscriber station of claim 22, wherein the first sequence is a first synchronization code sequence and the second sequence is a second synchronization code sequence.

29. The CDMA subscriber station of claim 22, wherein the frame is a first frame and the transmitting station is one of a plurality of transmitting stations, the controller being operable to facilitate measurements of downlink CDMA transmissions associated with the plurality of transmitting stations, the downlink CDMA transmissions being other than downlink CDMA transmissions associated with said one of the plurality of transmitting stations, the controller calculating a time difference of arrival based on the measurements, the measurements occurring during at least one time slot of a second frame, said downlink CDMA transmissions associated with said one of the plurality of transmitting stations are not transmitted during said at least one time slot of the second frame.

30. The CDMA subscriber station of claim 29, further comprising a GPS receiver configured to receive global positioning system (GPS) information and a transmitter to transmit the GPS information to the single transmitting station.

31. The CDMA subscriber station of claim 29, wherein the receiver is configured to receive location information from said one of the plurality of transmitting stations.

32. The CDMA subscriber station of claim 22, wherein the CDMA control channel includes symbols, and the CDMA subscriber station further includes a combiner configured to diversity combine the symbols of the CDMA control channel.

33. The CDMA subscriber station of claim 22, wherein the CDMA subscriber station is configured to conduct time division multiple access (TDMA) wireless communications.

34. The CDMA subscriber station of claim 32, wherein the controller is operable to delay at least one of the symbols prior to the diversity combining.

35. A method comprising:

receiving, with a code division multiple access (CDMA) subscriber station, a first signal during a first one of a plurality of time slots and a second signal during a second one of the plurality of time slots, the second signal carrying synchronization information, the plurality of time slots being included in a frame, and the first and second signals being transmitted by respective first and second ones of a plurality of antennas, the plurality of antennas being associated with a transmitting station;

detecting a first sequence carried by the first signal and a second sequence carried by the second signal, the first sequence being derived from a common bit sequence and the second sequence being derived from the common bit sequence;

diversity combining diversity transmitted data, the diversity transmitted data being carried by a CDMA control channel, said diversity combining utilizing first information derived from the first and second signals; and

deriving second information associated with the transmitting station, the synchronization information and the CDMA control channel being transmitted by the plurality of antennas of the transmitting station.

36. The method of claim 35, wherein both the first and second signals carry a combination sequence including the common bit sequence combined with a code sequence.

37. The method of claim 35, wherein the first and second sequences are different from one another.

38. The method of claim 35, wherein the detecting detects the common bit sequence.

39. The method of claim 38, further comprising selecting the detected common bit sequence associated with either the first one of the plurality of time slots or the second one of the plurality of time slots.

40. The method of claim 39, wherein the common bit sequence corresponds to a synchronization code.

41. The method of claim 38, wherein the common bit sequence is a synchronization code sequence, the CDMA subscriber station using the synchronization code sequence to synchronize to an output of the transmitting station.

42. The method of claim 37, wherein the code sequence is a synchronization code sequence.

43. A code division multiple access (CDMA) subscriber station comprising:

a receiver configured to receive a first synchronization code sequence during a first one of a plurality of time slots and a second synchronization code sequence during a second one of the plurality of time slots, the first and second synchronization code sequences being derived from a bit sequence, the plurality of time slots being included in a frame, the first and second synchronization code sequences being associated with a synchronization channel;

the receiver being further configured to diversity combine diversity transmitted data of a CDMA control channel, said diversity combining utilizing first information derived from the first and second synchronization code sequences, the CDMA channel and the synchronization channel being transmitted by a plurality of antennas associated with a base station; and

a controller configured to derive second information associated with the base station, and wherein the base station transmits the first or second synchronization code sequence from respective first and second ones of the plurality of antennas.

44. The CDMA subscriber station of claim 43, wherein both the first and second synchronization code sequences include a combination of the bit sequence and a code sequence.

45. The CDMA subscriber station of claim 43, wherein the first synchronization code sequence includes a combination of the bit sequence and a first code sequence and the second synchronization code sequence includes a combination of the bit sequence and a second code sequence, the first and second code sequences being different from one another.

46. The CDMA subscriber station of claim 43, wherein the receiver is configured to detect the bit sequence.

47. The CDMA subscriber station of claim 46, wherein the receiver selects either the detected bit sequence associated with either the first one of the plurality time slots or the second one of the plurality time slots.

48. The CDMA subscriber station of claim 46, wherein the bit sequence corresponds to a third synchronization code.

49. The CDMA subscriber station of claim 43, wherein the frame is a first frame and the base station is one of a plurality of base stations, the controller being operable to facilitate measurements of downlink CDMA transmissions associated with the plurality of base stations, the downlink CDMA transmissions being other than downlink CDMA transmissions associated with said one of the plurality of transmitting stations, the controller calculating a time difference of arrival based on the measurements, the measurements occurring in at least one time slot of a second frame, said downlink CDMA transmissions associated with said one of the plurality of base stations are not transmitted during said at least one time slot of the second frame.

50. The CDMA subscriber station of claim 49, further comprising a GPS receiver configured to receive global positioning system (GPS) information and a transmitter to transmit the GPS information to the single base station.

51. The CDMA subscriber station of claim 49 wherein the receiver is configured to receive location information from the said one of the plurality of base stations.

52. The CDMA subscriber station of claim 43, wherein the CDMA control channel includes symbols, and the CDMA subscriber station further includes a combiner configured to diversity combine the symbols of the CDMA control channel.

53. The CDMA subscriber station of claim 43, wherein the CDMA subscriber station is configured to conduct time division multiple access (TDMA) wireless communications.

54. The CDMA subscriber station of claim 52, further comprising a controller operable to delay one of the plurality of symbols prior to the combining said delay facilitating the diversity combining of the diversity transmitted data of the CDMA common control channel.

55. A spread spectrum receiver for use in a spread spectrum subscriber station, the spread spectrum receiver being configured to receive a common control channel transmitted from a base station, the base station including a plurality of first antennas, said spread spectrum receiver comprising:

a second antenna for receiving a spread-spectrum signal;

a detection circuit configured to detect a synchronization code over a plurality of time slots, within the spread spectrum signal carrying the synchronization code; and

a synchronization and timing controller configured to synchronize a common control channel processing circuit in response to the detected synchronization code;

the common control channel processing circuit comprising;

a code generator configured to generate a local copy of a spreading code associated with the common control channel;

a correlator configured to despread the received spread spectrum signal to generate a despread output, the correlator using the local copy of the spreading code, as a despread spread spectrum signal; and

a combiner configured to receive the despread output and to combine the despread output with a delayed version of the of the despread output as common control channel symbols.

56. The spread spectrum receiver of claim 55, wherein the spread spectrum receiver is a code division multiple access receiver.

57. The spread spectrum receiver of claim 55, wherein the plurality of time slots is a first plurality of time slots, the common control channel being transmitted over a second plurality of time slots, the second plurality of time slots being included in a time frame, and such that the base station does not transmit said spread spectrum signal during at least one of the second plurality of time slots, the spread spectrum receiver including:

a controller operable to facilitate taking measurements during the at least one of the second plurality of time slots.

58. The spread spectrum receiver of claim 57, wherein the measurements include measurements of CDMA signals for calculating a time difference of arrival.

59. The spread spectrum receiver of claim 58, wherein the controller is operable to send information related to the measurements to the base station.

60. The spread spectrum receiver of claim 59, wherein the receiver is configured to receive location information from the base station,the location information being derived from the measurements.

61. A code division multiple access (CDMA) subscriber station for use in a spread spectrum system, the CDMA subscriber station being configured to receive signals transmitted from a base station, the CDMA subscriber station comprising:

an antenna for receiving a spread spectrum signal over a plurality of time slots;

a detecting circuit configured to detect a plurality of synchronization codes, the synchronization codes being carried by the spread spectrum signal, each of the plurality of synchronization codes being associated with a corresponding one of the plurality of time slots;

a synchronization and timing controller configured to synchronize a common control channel processing circuit in response to the detected plurality of synchronization codes;

the common control channel processing circuit comprising;

a CDMA receiver configured to despread the received spread spectrum signal with a spreading code associated with the common control channel and generate a despread output; and

a combiner configured to receive the produced despread output with a delayed version of the despread output as conunon control channel symbols.

62. The CDMA subscriber station of claim 61, wherein the controller is operable to send information related to time difference of arrival facilitating measurements to the base station.

63. The CDMA subscriber station of claim 62, wherein the receiver is configured to receive location information from the base station, the location information being derived from the measurements.

64. The spread spectrum receiver of claim 61, wherein the plurality of time slots is a first plurality of time slots, the common control channel being transmitted over a second plurality of time slots, the second plurality of time slots being included in a time frame, such that the base station does not transmit said spread spectrum signal during at least one of the second plurality of time slots, the CDMA subscriber station further comprises:

a controller operable to facilitate taking measurements during the at least one of the second plurality of time slots.

65. A method for receiving a code division multiple access (CDMA) signal at a subscriber station, the CDMA signal being transmitted from a base station, the method comprising:

receiving a spread spectrum signal over a plurality of time slots;

detecting a plurality of synchronization codes, the synchronization codes being carried by the spread spectrum signal, each of the plurality of synchronization codes being associated with a corresponding one of the plurality of time slots; and

synchronizing processing of a diversity transmitted common control channel in response to the detected plurality of synchronization codes;

the processing of the diversity transmitted common control channel comprising;

despreading the received spread spectrum signal to generate an output despread signal; and

combining the output despread signal with a delayed version of the output despread signal as common control channel symbols.

66. The method of claim 65, wherein the plurality of time slots is a first plurality of time slots, the common control channel being transmitted over a second plurality of time slots, the second plurality of time slots being included in a time frame, such that the base station does not transmit said spread spectrum signal during at least one of the second plurality of time slots, the method further comprises:

taking measurements during the at least one of the second plurality of time slots.

67. A wireless code division multiple access (CDMA) subscriber station for use in a terrestrial wireless code division multiple access communication system, the subscriber station comprising:

a receiver that receives a diversity transmitted synchronization channel, the diversity transmitted synchronization channel carrying a plurality of synchronization codes, each of the plurality of synchronization codes being associated with a corresponding one of a plurality of time slots, the receiver being configured to detect the plurality of synchronization codes, and wherein the receiver despreads a diversity transmitted common control channel with a corresponding CDMA code, the despread common control channel carrying symbols;

a diversity combiner that combines the symbols of the despread common control channel with symbols associated with a delayed version of the despread common control channel to produce combined symbols of tho common control channel; and

a synchronization controller that controls the receiver and the diversity combiner so that diversity combining of the diversity transmitted common control channel is facilitated.

68. In a code division multiple access (CDMA) cellular system that utilizes transmission diversity by transmitting a plurality of data signals in a predetermined time frame format comprising a plurality of sequential time slots per time frame, a method for receiving data from a transmitting station by a receiving station comprising:

receiving a first signal from a first antenna of a first transmitting station corresponding to at least one synchronization symbol data in a first time slot of the time frame format;

receiving a second signal from a second antenna of said first transmitting station corresponding to the same at least one synchronization symbol in a second time slot of the time frame format, said second time slot occurring after said first time slot relative to the time frame format; and

utilizing the received first and second data signal to synchronize the receiving station to the transmitting station.

69. The method in accordance with claim 68, wherein the first and second signal comprise a code and said first signal and said second signal correspond to said code.

70. A receiving station for a code division multiple access (CDMA) cellular system that utilizes transmission diversity, a plurality signals being transmitted in the CDMA cellular system, each of the plurality of signals being in a predetermined time frame format, the predetermined time frame format comprising sequential time slots and a plurality of frames, each of the plurality of frames being associated with at least one of the time slots, the plurality of signals for communicating data, the receiving station comprising:

a receiver configured to receive a first one of the plurality of signals from a first antenna of a first transmitting station, the first one of the plurality of signals carrying at least one synchronization symbol in a first one of the time slots, and the receiver is also configured to receive a second one of the plurality of signals from a second antenna of said first transmitting station, the second one of the plurality of signals carrying the at least one synchronization symbol in a second one of the time slots, said second one of the time slots occurring after said first one of the time slots relative to the time frame format, and

said receiver is configured to utilize the first and second ones of the plurality of signals to facilitate communication with said first transmitting station, the first and second ones of the plurality of signals facilitating reception, by said receiver, of a diversity transmitted common control channel.

71. The receiving station in accordance with claim 70, wherein the first and second signals comprise a code.

72. The receiving station in accordance with claim 70, wherein the receiver receives the diversity transmitted common control channel by using the at least one synchronization symbol recovered from the first one of the plurality of signals or the second one of the plurality of signals.

73. The receiving station in accordance with claim 70, wherein the receiving station determines a time difference in chips between CDMA data signals received from the first and second antennas to facilitate determining a location of the receiving station.

74. The receiving station in accordance with claim 73, further comprising a transmitter, the transmitter being configured to transmit location information including the time difference to the cellular system.

75. The receiving station in accordance with claim 74, wherein the location information is encrypted prior to transmission.

76. The receiving station in accordance with claim 70, wherein the diversity transmitted common control channel is supplied over a plurality of said time slots, said plurality of said time slots being associated with one of the plurality of frames.

77. The receiving station in accordance with claim 70 configured to conduct both Code Division Multiple Access (CDMA) wireless communications and Time Division Multiple Access (TDMA) wireless communications.

78. The receiving station in accordance with claim 76, wherein the diversity transmitted control channel is not transmitted in selected ones of the time slots and the receiving station is configured to take measurements during the selected ones of the time slots.