摘要:
A dispatch system generally provides a means for collecting destination information, selecting a dispatch assignment (104) to be dispatched to the destination (102) and dispatching the selected assignment. In situations where the response time of the assignment is a critical factor, selecting the assignment with the shortest response time is desired. An improved method for improving response time of an assignment with the shortest response time incorporates assignment location, a road condition associated with each assignment, and the traffic conditions associated with each assignment. Event information is also considered in determining the best route and travel time from the mobile entity to the destination.
摘要:
A mobile subscriber unit (MS) location method and system in a spread spectrum channel coding system uses a known spread spectrum location beacon channel (34) that is time division multiplexed with normal code division multiplexed channels (36). Each base station (12, 14 and 16) in a defined service area transmits the known time division multiplexed spread spectrum location beacon signal (34), such as a known location channel, as a spread spectrum location beacon signal at a same time interval. Mobile subscriber units (18) receive the spread spectrum location beacon signal (34) time division multiplexed with the normal CDMA channels (36) and determine their own location using location techniques such as trilateration. Preferably, all of a base station's transmit power is assigned to this special known location channel (34) during transmission.
摘要:
Orthogonal transmit diversity is implemented by employing a data splitter (803) to subdivide channel information (801) into at least a first portion of bits (802) and a second portion of bits (804). Each portion is spread with its own Walsh code for eventual transmission to a mobile station via a predetermined carrier frequency. When the number of bits in the first and second portion (802, 804) are small, separate Walsh codes are used to maintain orthogonality. When the number of bits in the first and second portion (802, 804) are relatively large, a time-division multiplex transmission is used to maintain orthogonality. A controller (809) controls the subdivision of the channel information and also an interleaver (308) to further enhance the effects of the diversity transmission. Control information related to the subdivision is transmitted to the mobile station so the channel information can be accurately reconstructed prior to decoding.
摘要:
A frequency-hopping communication system preempts certain burst frequency assignments. The communication system is capable of communicating to mobile stations (114, 115) via a radio channel (121) in a TDM/TDMA mode. A plurality of mobile stations are assigned burst frequencies for transmission during timeslots of the TDMA system. To support additional mobile stations without additional burst frequencies, the communication system preempts the burst frequency assignment from the plurality of mobile stations, and utilizes the preempted assignment to support communication to the additional mobile stations.
摘要:
In a radio frequency communication system (100), infrastructure transceivers operate in a configuration mode (301-306) and an active mode (307). When in the configuration mode, a given infrastructure transceiver (106-109) derives information regarding RF operating circumstances proximal to the infrastructure transceiver. The information regarding the RF operating circumstances, information regarding the infrastructure transceiver itself, and optionally information regarding present location of the infrastructure transceiver, is transmitted to a communication system configuration server (105). In response, information regarding operation of the infrastructure transceiver is received by the infrastructure transceiver. When in the given infrastructure transceiver is in the active mode, the information regarding operation of the infrastructure transceiver is used to support communications in the RF communication system. With each infrastructure transceiver operating in this manner, the radio frequency communication system can be automatically configured.
摘要:
A method of maintaining call quality in a communication system by communicating between a base site (101) and a communication unit (113) on a first channel. The communication unit (113) monitors the downlink communication signal (116) transmitted by the base site (101) and determines a characteristic of the first channel. The communication unit (113) is then handed off to a second channel having a less aggressive reuse pattern, based on the characteristic of the first channel.
摘要:
To mitigate the adverse affects of the load imbalance phenomenon prevalent in spread spectrum, multi-carrier wireless communication systems, the system beneficially employs the use of handoff as a means for balancing the call traffic (commonly referred to as "load") among a plurality of carriers within the communication system. The multi-carrier wireless communication system monitors a plurality of metrics corresponding to the loading of each of the plurality of carriers in the communication system and, based upon the metrics, will handoff call traffic to and between the plurality of carriers, thereby mitigating the adverse effects associated with the load imbalance, in accordance with the invention.
摘要:
An RF cellular communication system employing offset frame synchronization between cells, any cell being omni-directional or directional, such that a frame at one cell is offset by an integral number of frames from another cell; the system incorporating multiplexed speech transcoding of traffic channels from multiple cells while supporting stringent delay requirements. Offset frame synchronization for providing rapid mobile assisted handoff.
摘要:
A smart card (100) is equipped with an internal time-of-day clock and calendar (106). Between the smart card (100) and a subscriber unit (209, 300), into which it is inserted, there is a communication of the subscriber's identity and a negotiated agreement for how long the subscriber unit (209, 300) is to maintain the transferred identity. For that duration of time, the subscriber unit (209, 300) is enabled with the subscriber's identity, and the smart card is essentially "dumb," and therefore unusable until that duration has elapsed.
摘要:
A communication unit for use in a communication system is provided which includes a hopping mechanism which hops communication frames over a plurality of carrier frequencies according to a predetermined hopping pattern. At least one of the communication frames preferably includes a synchronization channel time slot having data bits from which the predetermined hopping pattern may be derived. In addition, a communication unit is provided which includes a signal acquisition mechanism for initially acquiring a predetermined hopping pattern that specifies the sequence over which hop frames are hopped over a plurality of carrier frequencies. Also, this communication unit includes a hopping mechanism for hopping receiving frequency according to the predetermined hopping pattern such that a control channel may be detected. In an alternative embodiment, either communication unit may derive the predetermined hopping pattern from detected global position satellite information.