摘要:
A variable rate transmission system transmits a variable rate data packet including an accompanying rate indication signal indicative of the transmission rate of the variable data packet. The data packet can be spread using a long pseudonoise (PN) code, the mask of which can be selected in accordance with the transmission rate of the variable rate data packet. A preamble, providing the transmission rate, can be punctured into an outgoing pilot signal. The rate indication signal can be encoded in accordance with a set of orthogonal functions that are part of the indication of the transmission rate of the data packet.
摘要:
Techniques to efficiently attempt acquisition of a packet data system (e.g., an IS-856 system). If a terminal has acquired one or more channels in a voice/data system (e.g., an IS-2000 system), then it can attempt acquisition on channels in the packet data system that are co-located with the acquired channels in the voice/data system. Multiple acquisition modes may be used, and on-going acquisition attempts on the co-located channels may be performed using one acquisition mode at a time in order to reduce power consumption. Acquisition attempts may be performed in a “ping-pong” manner to improve the likelihood of acquisition. For a ping-pong search, an acquisition attempt is made on the most recently acquired channel prior to an acquisition attempt on each of the remaining channels. Received signal strength estimates may also be obtained for selected channels and may be used to determine whether or not to attempt acquisition on these channels.
摘要:
A method and system for reverse link transmit beam-forming. One method comprises using a plurality of antennas at an access terminal to wirelessly transmit signals to one or more base stations; receiving an input indicating a reverse link signal quality at the one or more base stations; and adjusting at least one of a gain and a phase of a signal to be transmitted on one or more antennas. The input may be a reverse power control (RPC) value sent from one or more base stations or a measurement of the closed-loop pilot transmit power.
摘要:
A system and method for providing group communication services is disclosed. Each of a plurality of group communication devices coverts media, such as video, audio, image and/or data into data packets suitable for transmission over a data network, such as the Internet. The data packets are selectively transmitted through the data network to a communications manager. The communications manager acts as a configurable switch, allowing communications from any communication device to be selectively routed to the plurality of communication devices based on the types of the communication devices and/or the requests received from the corresponding users. The communications manager further allows users of other communication systems and devices to participate in group communications with each other.
摘要:
Embodiments disclosed herein relate to methods and systems for server selection during feedback channel impairment in wireless communications. The feedback channel may be provided by a data rate control (DRC) channel, transmitted from an access terminal to an access network relating the selected serving sector (DRC cover) and the desired data rate (DRC rate) for transmission on forward link. During DRC cover erasure (e.g., due to channel impairment), a data source control (DSC) channel may be used as complimentary information to assist the DRC erasure mapping decision at the access network.
摘要:
Adaptive De-Jitter Buffer for Voice over IP (VoIP) for packet switch communications. The de-jitter buffer methods and apparatus presented avoid playback of underflows while balancing end-to-end delay. In one example, the de-jitter buffer is recalculated at the beginning of each talkspurt. In another example, talkspurt packets are compressed upon receipt of all remaining packets.
摘要:
Techniques to efficiently attempt acquisition of a packet data system (e.g., an IS-856 system). If a terminal has acquired one or more channels in a voice/data system (e.g., an IS-2000 system), then it can attempt acquisition on channels in the packet data system that are co-located with the acquired channels in the voice/data system. Multiple acquisition modes may be used, and on-going acquisition attempts on the co-located channels may be performed using one acquisition mode at a time in order to reduce power consumption. Acquisition attempts may be performed in a “ping-pong” manner to improve the likelihood of acquisition. For a ping-pong search, an acquisition attempt is made on the most recently acquired channel prior to an acquisition attempt on each of the remaining channels. Received signal strength estimates may also be obtained for selected channels and may be used to determine whether or not to attempt acquisition on these channels.
摘要:
An optimum combiner that reduces the amount of interference imposed upon a first base station by transmissions of other base stations within the same communication system. Two antennas are used to receive transmissions within a receiving station. A rake receiver is coupled to each antenna. By optimally combining the signals that are received by each independent finger of the rake receiver, interference that is correlated between a finger associated with the first antenna and a finger associated with the second antenna can be minimized with respect to the desired signal. Optimum combining requires determination of optimum combining coefficients.
摘要:
Techniques to support handover of a terminal from a source base station to a target base station are described. In one design, a determination is made whether a change in personality is requested by the terminal. If the answer is ‘Yes’, then the personality of the terminal may be switched by sending one or more appropriate messages. The connection and RLP for the terminal may be reset due to the change in personality. A buffer of data reported by the source base station as being served to the terminal (e.g., no NAK was sent) may be saved by a BSC/PCF. The buffer of data may be sent to the target base station when handover occurs. New data may thereafter be sent to the target base station. This buffer of duplicate data may avoid both loss of data and retransmission timeout by TCP during the handover.
摘要:
Embodiments disclosed herein relate to methods and systems for providing improved position-location (e.g., time-of-arrival) measurement and enhanced position location in wireless communication systems. In an embodiment, an access point may replace information (e.g., data) transmission by a “known” transmission (or “reference transmission”) at a predetermined time known to access terminals in the corresponding sectors. The access terminals may use the received reference transmission to perform a position-location measurement, and report back the measured information. The access point may also send a reference transmission on demand, e.g., in response to a request from an access terminal in need for a location-based service.