초록 ▼

The present invention relates to a system and method for providing radio frequency communication of data collected by a multiplicity of mobile transceiver units to a base transceiver. The system comprises the base transceiver and the mobile transceiver units being selectively operable at limited and

The present invention relates to a system and method for providing radio frequency communication of data collected by a multiplicity of mobile transceiver units to a base transceiver. The system comprises the base transceiver and the mobile transceiver units being selectively operable at limited and increased data rates. The mobile units respond to transmissions by the base transceiver, and have means to evaluate the feasibility of responding at the increased data rate. The base transceiver effects a communication link with one or more mobile units. The mobile units for which a communication link has not been established receives the transmissions of the mobile units with which a communication link has been established. The mobile units evaluate for consistent reception of transmissions to one or more transceiver units. The mobile units which consistently receive transmissions at the increased data rate respond at the increased data rate when communication is directed thereto.

대표청구항 ▼

The invention claimed is: 1. A radio frequency data communication system for transmission of data collected by a multiplicity of mobile transceiver units, to a base transceiver, comprising: a base transceiver selectively operable at a limited data rate and at an increased data rate, the base transc

The invention claimed is: 1. A radio frequency data communication system for transmission of data collected by a multiplicity of mobile transceiver units, to a base transceiver, comprising: a base transceiver selectively operable at a limited data rate and at an increased data rate, the base transceiver supporting spread spectrum communications; the multiplicity of mobile transceiver units selectively operable at the limited data rate and at the increased data rate, the mobile transceiver units supporting spread spectrum communications; said mobile transceiver units responsive to transmissions by said base transceiver, and having control means therein to evaluate the feasibility of responding at said increased data rate; said base transceiver effecting a communication link with one or more of said mobile transceiver units; said mobile transceiver units for which a communication link with said base transceiver has not been established receiving the transmissions of said base transceiver to said mobile transceiver units with which a communication link has been established; said mobile transceiver units evaluating for consistent reception of said transmissions to said one or more transceiver units; said mobile units which consistently receive transmissions at the increased data rate responding to the base transceiver at said increased data rate when said base transceiver directs communication to said mobile unit. 2. The system of claim 1 wherein said mobile transceiver units independently evaluate transmissions from the base transceiver to said one or more mobile transceiver units having a communications link with said base transceiver. 3. The system of claim 1 wherein each mobile transceiver unit remains to receive data while no communication link is established between said mobile transceiver unit and the base transceiver. 4. The system of claim 1 wherein the base transceiver transmits packets of data to said one or more mobile transceiver units having a communication link with the base transceiver, each mobile transceiver unit with which a communication link has not been established: attempting to receive packets of data transmitted by the base transceiver to said one or more units having a communication link with the base transceiver; each mobile transceiver unit with which a communication link has not been established; evaluating receipt of packets of data at the increased data rate and at the limited data rate. 5. The system of claim 1 wherein said mobile transceiver units which have not established a communication link with said base receiver receiving polling signals transmitted by said base transceiver at the increased data rate: said mobile transceiver units evaluating for constant reception of said polling signals, to determine the feasibility of successful communication with said base transceiver at the increased data rate. 6. The system of claim 1 wherein said mobile transceiver sampling data transmitted to said one or more of said mobile transceiver units at said limited data rate and at said increased data rate. 7. The system of claim 1 wherein the base transceiver and/or at least one of the multiplicity of mobile transceiver units are capable of being selectivity operable at a first spreading code length and a second spreading code length for use in the spread spectrum communications, the first spreading code length being shorter than the second spreading code length. 8. The system of claim 1 wherein the base transceiver and/or at least one of the multiplicity of mobile transceiver units are capable of being selectivity operable at a first frequency hopping rate and at a second frequency hopping rate for use in the spread spectrum communications, the first frequency hopping rate being slower than the second frequency hopping rate. 9. A wireless data communication system, comprising: a base station transceiver capable of communication with a plurality of mobile transceivers via a wireless network, each of the plurality of mobile transceivers employing one of a first data rate and a second data rate for transmission, based upon an evaluation of radio frequency operating conditions of the wireless network, the first data rate being higher than the second data rate; and the base station transceiver transmitting one or more messages usable by the plurality of mobile transceivers in performing the evaluation of radio frequency operating conditions of the wireless network, wherein the evaluation of radio frequency operating conditions of the wireless network comprises computing a weighted signal strength measurement, the weighting giving emphasis to lower signal strength measurements of fading signals, and wherein the base station transceiver and the mobile transceivers support the spread spectrum communications. 10. The system of claim 9 wherein the computing of the weighted signal strength measurement in which the weighting gives emphasis to the lower signal strength measurements of fading signals is part of evaluating a signal strength measurement. 11. The system of claim 9 wherein the evaluation of radio frequency operating conditions of the wireless network comprises evaluating an error rate. 12. The system of claim 11 wherein evaluating an error rate comprises evaluating at least one of a bit error rate (BER), a message error rate, a rate of failure to receive a positive acknowledgement, a rate of failure to receive a response to a transmission, and a timeout of a communications protocol timer. 13. The system of claim 9 wherein the one or more messages comprise a polling message. 14. The system of claim 9 wherein the one or more messages comprise a test signal. 15. The system of claim 9 wherein at least a portion of the one or more messages is transmitted at the first data rate. 16. The system of claim 9 wherein at least a portion of the one or more messages is transmitted on a periodic basis. 17. The system of claim 9 wherein each of the one or more messages has an associated type, and wherein messages of a predetermined type are always transmitted by the base station transceiver at the second data rate. 18. The system of claim 9 wherein the base station transceiver employs one of the first data rate and the second data rate for transmission, based upon an evaluation of operation of the wireless network. 19. The system of claim 18 wherein evaluation of operation of the wireless network comprises evaluating an error rate. 20. The system of claim 19 wherein evaluating an error rate comprises evaluating at least one of a bit error rate (BER), a message error rate, a rate of failure to receive a positive acknowledgement, a rate of failure to receive a response to a transmission, and a timeout of a communications protocol timer. 21. The system of claim 9 wherein at least a portion of the one or more messages is transmitted at the first data rate to evaluate whether operation at the first data rate is sustainable. 22. The system of claim 9 wherein at least one of the plurality of mobile transceivers is capable of adjusting spreading code length for use in the spread spectrum communications. 23. The system of claim 9 wherein at least one of the plurality of mobile transceivers is capable of switching between a first frequency hopping rate and at a second frequency hopping rate for use in the spread spectrum communications, the first frequency hopping rate being slower than the second frequency hopping rate. 24. A method of determining a data rate in a wireless communication network, comprising: receiving at least one data message via the wireless communication network, the wireless communications network supporting spread spectrum communications; evaluating wireless communication network operating conditions based upon the received at least one data message, wherein evaluating the wireless communication network operating conditions comprises computing a weighted signal strength measurement, the weighting giving emphasis to lower signal strength measurements of fading signals; selecting one of a first data rate and a second data rate based upon the evaluation of wireless communication network operating conditions, the second data rate being higher than the first data rate; and transmitting at least one data message via the wireless communication network using the selected data rate. 25. The method of claim 24 wherein the computing of the weighted signal strength measurement in which the weighting gives emphasis to the lower signal strength measurements of fading signals are part of evaluating a signal strength measurement. 26. The method of claim 24 wherein evaluating wireless communication network operating conditions comprises evaluating an error rate. 27. The method of claim 26 wherein evaluating an error rate comprises evaluating at least one of a bit error rate (BER), a message error rate, a rate of failure to receive a positive acknowledgement, a rate of failure to receive a response to a transmission, and a timeout of a communications protocol timer. 28. The method of claim 24 wherein the received at least one data message comprises a polling message. 29. The method of claim 24 wherein the received at least one data message comprises a test signal. 30. The method of claim 24 wherein at least a portion of the received at least one data message is transmitted at the second data rate. 31. The method of claim 24 wherein at least a portion of the received at least one data message is always received at the first data rate. 32. The method of claim 24 wherein the transmitted at least one data message comprises the selected data rate. 33. The method of claim 24 wherein the wireless communication network is a radio frequency communication network. 34. The method of claim 24 wherein at least a portion of the received at least one data message is transmitted at the second data rate to evaluate whether operation of the wireless communication network at the second data rate is sustainable. 35. The method of claim 24 wherein the selecting of the first data rate and the second data rate is effected at least by selecting between a first spreading code length and a second spreading code length for use in the spread spectrum communications, the first spreading code length being shorter than the second spreading code length. 36. The method of claim 24 wherein the selecting of the first data rate and the second data rate is effected at least by selecting between a first frequency hopping rate and at a second frequency hopping rate for use in the spread spectrum communications, the first frequency hopping rate being slower than the second frequency hopping rate. 37. One or more circuits in a mobile wireless communication device, comprising: receiver circuitry capable of receiving digital information communicated via a radio frequency network; at least one processor that evaluates operating conditions of the radio frequency network, the evaluating of operating conditions of the radio frequency network comprises computing a weighted signal strength measurement, the weighting giving emphasis to lower signal strength measurements of fading radio frequency signals, the at least one processor selecting one of a first data rate and a second data rate based upon the evaluation, the second data rate being higher than the first data rate; and transmitter circuitry capable of transmitting digital information at the selected data rate, via the radio frequency network, the transmitter circuitry being operatively coupled to the at least one processor, wherein the mobile wireless communication device supports spread spectrum communications. 38. The one or more circuits of claim 37 further comprising signal strength measurement circuitry operatively coupled to the receiver circuitry, the signal strength measurement circuitry producing an indication of signal strength of a received radio frequency signal, the indication of signal strength available for use by the at least one processor. 39. The one or more circuits of claim 37 wherein the computing of the weighted signal strength measurement in which the weighting gives emphasis to the lower signal strength measurements of fading radio frequency signals is part of evaluating a signal strength measurement. 40. The one or more circuits of claim 37 wherein evaluating operating conditions of the radio frequency network comprises evaluating an error rate. 41. The one or more circuits of claim 40 wherein evaluating an error rate comprises evaluating at least one of a bit error rate (BER), a message error rate, a rate of failure to receive a positive acknowledgement, a rate of failure to receive a response to a transmission, and a timeout of a communications protocol timer. 42. The one or more circuits of claim 37 wherein evaluating operating conditions of the radio frequency network is performed during reception of one or more messages. 43. The one or more circuits of claim 42 wherein at least a portion of the one or more messages is received on a substantially regular period. 44. The one or more circuits of claim 42 wherein at least a portion of the one or more messages comprise a test signal. 45. The one or more circuits of claim 42 wherein at least a portion of the one or more messages comprise a polling message. 46. The one or more circuits of claim 42 wherein at least a portion of the one or more messages is received at the second data rate. 47. The one or more circuits of claim 42 wherein each of the one or more messages has an associated type, and wherein messages of a predetermined type are always received at the first data rate. 48. The one or more circuits of claim 42 wherein at least a portion of the one or more messages is received at the second data rate to evaluate whether operation of the radio frequency network at the second data rate is sustainable. 49. The one or more circuits of claim 37 wherein the receiver and the transmitter operate on the same radio frequency. 50. The one or more circuits of claim 37 wherein the at least one processor is capable of selecting one of a first spreading code length and a second spreading code length for use in the spread spectrum communications, the first spreading code length being shorter than the second spreading code length. 51. The one or more circuits of claim 37 wherein the at least one processor is capable of selecting one of a first frequency hopping rate and at a second frequency hopping rate for use in the spread spectrum communications, the first frequency hopping rate being slower than the second frequency hopping rate. 52. A wireless data communication system, comprising: a mobile transceiver that, during operation, communicates with a base station transceiver via a wireless network, the mobile transceiver employing one of a first data rate and a second data rate for transmission, based upon an evaluation of radio frequency operating conditions of the wireless network, the first data rate being higher than the second data rate; and the mobile transceiver receiving one or more messages usable in performing the evaluation of radio frequency operating conditions of the wireless network, wherein evaluation of radio frequency operating conditions of the wireless network comprises evaluating a signal strength measurement, wherein evaluating a signal strength measurement comprises computing a weighted signal strength measurement, the weighting giving emphasis to lower signal strength measurements of fading signals, and wherein the mobile transceiver and the base station transceiver support spread spectrum communications. 53. The system of claim 52 wherein evaluation of radio frequency operating conditions of the wireless network comprises evaluating an error rate. 54. The system of claim 53 wherein evaluating an error rate comprises evaluating at least one of a bit error rate (BER), a message error rate, a rate of failure to receive a positive acknowledgement, a rate of failure to receive a response to a transmission, and a timeout of a communications protocol timer. 55. The system of claim 52 wherein the one or more messages comprise a polling message. 56. The system of claim 52 wherein the one or more messages comprise a test signal. 57. The system of claim 52 wherein at least a portion of the one or more messages is transmitted at the first date rate. 58. The system of claim 52 wherein at least a portion of the one or more messages is transmitted on a periodic basis. 59. The system of claim 52 wherein each of the one or more messages has associated type, and wherein messages on a predetermined type are always received by the mobile transceiver at the second data rate. 60. The system of claim 52 wherein the mobile transceiver selects one of the first date rate and the second data rate for transmission, based upon an evaluation of operation of the wireless network. 61. The system of claim 60 wherein evaluation of operation of the wireless network comprises evaluating an error rate. 62. The system of claim 61 wherein evaluating an error rate comprises evaluating at least one of a bit error rate (BER), a message error rate, a rate of failure to receive a positive acknowledgment, a rate of failure to receive a response to a transmission, and a timeout of a communications protocol timer. 63. The system of claim 52 wherein at least a portion of the one or more messages is transmitted at the first data rate to evaluate whether operation at the first data rate is sustainable. 64. The system of claim 52 wherein the first data rate and the second data rate are effected at least by adjusting a length of a spreading code for use in the spread spectrum communications. 65. The system of claim 52 wherein the first data rate and the second data rate are effected at least by adjusting a frequency hopping rate for use in the spread spectrum communications. 66. A wireless data communication system, comprising: a mobile device that, during operation, communicates with a base station via a wireless network, the mobile device employing one of a first data rate and a second data rate for transmission, based upon an evaluation of a radio frequency operating conditions of the wireless network, the first data rate being higher then the second data rate, and the mobile device receiving one or more messages usable in performing the evaluation of radio frequency operating conditions of the wireless network, wherein the evaluation of radio frequency operating conditions of the wireless network comprises computing a weighted signal strength measurement, the weighting giving emphasis to lower signal strength measurements of fading signals, and wherein the mobile device and the base station support spread spectrum communications. 67. The system of claim 66 wherein the computing of the weighted signal strength measurement in which the weighting gives emphasis to the lower signal strength measurements of fading signals is part of evaluating a signal strength measurement. 68. The system of claim 66 wherein evaluation of radio frequency operating conditions of the wireless network comprises evaluating an error rate. 69. The system of claim 68 wherein evaluating an error rate comprises evaluating at least one of a bit error rate (BER), a message error rate, a rate of failure to receive a positive acknowledgement, a rate of failure to receive a response to a transmission, and a timeout of a communications protocol timer. 70. The system of claim 66 wherein the one or more messages comprise a polling message. 71. The system of claim 66 wherein the one or more messages comprise a test signal. 72. The system of claim 66 wherein at least a portion of the one or more messages is transmitted at the first data rate. 73. The system of claim 66 wherein at least a portion of the one or more messages is transmitted on a periodic basis. 74. The system of claim 66 wherein each of the one or more messages has an associated type, and wherein messages of a predetermined type are always received by the mobile transceiver at the second data rate. 75. The system of claim 66 wherein the mobile device selects one of the first data rate and the second data rate for transmission, based upon an evaluation of operation of the wireless network. 76. The system of claim 75 wherein evaluation of operation of the wireless network comprises evaluating an error rate. 77. The system of claim 76 wherein evaluating an error rate comprises evaluating at least one of a bit error rate (BER), a message error rate, a rate of failure to receive a positive acknowledgement, a rate of failure to receive a response to a transmission, and a timeout of a communications protocol timer. 78. The system of claim 66 wherein at least a portion of the one or more messages is transmitted at the first data rate to evaluate whether operation at the first data rate is sustainable. 79. The system of claim 66 wherein the wireless data communication system is capable of employing a length-adjustable spreading code for use in the spread spectrum communications. 80. The system of claim 66 wherein the wireless data communication system is capable of employing an adjustable frequency hopping rate for use in the spread spectrum communications. 81. One or more circuits in a mobile wireless communications device, comprising: at least one processor that evaluates operating conditions of a radio frequency network, the evaluating of operating conditions of the radio frequency network comprises computing a weighted signal strength measurement, the weighting giving emphasis to lower signal strength measurements of fading radio frequency signals, the at least one processor selecting one of a first data rate and a second data rate based upon the evaluation, the first data rate being lower than the second data rate; and the at least one processor causing transmitter circuitry to transmit information at the selected data rate, via the radio frequency network, wherein the mobile wireless communications device supports spread spectrum communications. 82. The one or more circuits of claim 81 further comprising signal strength measurement circuitry operatively coupled to receiver circuitry, the signal strength measurement circuitry producing an indication of signal strength of a received radio frequency signal, the indication of signal strength available for use by the at least one processor. 83. The one or more circuits of claim 81 wherein the computing of the weighted signal strength measurement in which the weighting gives emphasis to the lower signal strength measurements of fading radio frequency signals is part of evaluating a signal strength measurement. 84. The one or more circuits of claim 81 wherein evaluating operating conditions of the radio frequency network comprises evaluating an error rate. 85. The one or more circuits of claim 84 wherein evaluating an error rate comprises evaluating at least one of a bit error rate (BER), a message error rate, a rate of failure to receive a positive acknowledgement, a rate of failure to receive a response to a transmission, and a timeout of a communications protocol timer. 86. The one or more circuits of claim 81 wherein evaluating operating conditions of the radio frequency network is performed during reception of one or more messages. 87. The one or more circuits of claim 86 wherein at least a portion of the one or more messages is received on a substantially regular period. 88. The one or more circuits of claim 86 wherein at least a portion of the one or more messages comprise a test signal. 89. The one or more circuits of claim 86 wherein at least a portion of the one or more messages comprise a polling message. 90. The one or more circuits of claim 86 wherein at least a portion of the one or more messages is received at the second data rate. 91. The one or more circuits of claim 86 wherein each of the one or more messages has an associated type, and wherein messages of a predetermined type are always received at the relatively lower first data rate. 92. The one or more circuits of claim 86 wherein at least a portion of the one or more messages is received at the second data rate to evaluate whether operation of the radio frequency network at the second data rate is sustainable. 93. The one or more circuits of claim 81 wherein a receiver and a transmitter operate on the same radio frequency. 94. The one or more circuits of claim 81 wherein the spread spectrum communications employs a length-adjustable spreading code. 95. The one or more circuits of claim 81 wherein the spread spectrum communications employs an adjustable frequency hopping rate. 96. One or more circuits in a mobile wireless communications device, comprising: at least one processor that evaluates operating conditions of a radio frequency network, the evaluating of operating conditions of the radio frequency network comprises computing a weighted signal strength measurement, the weighting giving emphasis to lower signal strength measurements of fading radio frequency signals, the at least one processor choosing between a higher data throughput and a lower data throughput based upon the evaluation, the higher data throughput and the lower data throughput being effected at least by employing different lengths of a length-adjustable spreading code for use in the spread spectrum communications; and the at least one processor causing transmitter circuitry to transmit information at the chosen data throughput via the radio frequency network, wherein the mobile wireless communications device supports spread spectrum communications in the radio frequency network. 97. One or more circuits in a mobile wireless communications device, comprising: at least one processor that evaluates operating conditions of the radio frequency network, the evaluating of operating conditions of the radio frequency network comprises computing a weighted signal strength measurement, the weighting giving emphasis to lower signal strength measurements of fading radio frequency signals, the at least one processor choosing between a higher data throughput and lower data throughput based upon the evaluation, the higher data throughput and the lower data throughput being effected at least by employing different frequency hopping rates for use in the spread spectrum communications; and the at least one processor causing transmitter circuitry to transmit information at the chosen data throughput via the radio frequency network, wherein the mobile wireless communications device supports spread spectrum communications in the radio frequency network.