Abstract: The present invention makes it possible to increase a data rate between a transmitter and receiver using a multiple-input, multiple-output radio frequency channel. A multiple-stream, multiple-antenna receiver measures a composite channel between a multiple-antenna transmitter and a multiple-antenna receiver to produce a composite channel measurement. The receiver selects a plurality of antenna array weight sets for use in the multiple-antenna transmitter in response to the composite channel measurement, where each antenna array weight set is associated with one of multiple data streams. Information describing the plurality of antenna array weight sets for use in the multiple-antenna transmitter are then transmitted.

Abstract: A method for and wireless communications unit adapted for measuring transmission performance for a signal emanating from an antenna is discussed. The wireless communications unit includes a receiver for receiving the signal in a first and a second time interval to provide, respectively, a first and a second signal; and a channel processor for assessing a relative channel metric corresponding to the first and second signal, the relative channel metric indicative of the transmission performance of a transmission mode.

Abstract: A method 600 of selecting an ARQ method for retransmitting a data frame based on an accumulated signal to noise ratio (SNR) of systematic bits in the data frame at a receiving unit 508. The sending unit 500 tracks the accumulated SNR of systematic bits by using channel SNR measurement reports sent by the receiving unit 508. The method utilizes Chase combining of re-transmitted systematic bits (via Partial incremental redundancy transmissions) until the accumulated SNR of the systematic bits has reached a suitable value, and then switches to sending only parity bits (via Full incremental redundancy) in retransmissions. In addition, the method alters the allocation of resources, such as code power, to provide only that necessary for successful decoding of the transmitted frame. The sending unit 500 informs the receiving unit 508 of the type of transmission, number of the transmission and/or resource allocation associated with the data frame.

Abstract: The present invention makes it possible to increase a data rate between a transmitter and receiver using a multiple-input, multiple-output radio frequency channel. A multiple-stream, multiple-antenna receiver measures a composite channel between a multiple-antenna transmitter and a multiple-antenna receiver to produce a composite channel measurement. The receiver selects a plurality of antenna array weight sets for use in the multiple-antenna transmitter in response to the composite channel measurement, where each antenna array weight set is associated with one of multiple data streams. Information describing the plurality of antenna array weight sets for use in the multiple-antenna transmitter are then transmitted.

Abstract: In a method for wireless data communication between a base station and a subscriber unit in a wireless communication system, groups of symbols of an input data stream are commutated to produce a plurality of commutated data streams. The plurality of commutated data streams are then transformed to produce a plurality of transformed data streams. Next, each transformed data stream is spread with a selected one of a plurality of spreading codes to produce a plurality of antenna signals. Finally, each of the plurality of antenna signals is transmitted using a selected one of a plurality of spaced apart antennas, wherein the plurality of spaced apart antennas are spaced apart to provide transmit diversity. In one embodiment, the transform is a space-time transform.

Abstract: A CDMA communication system (400) includes a plurality of base stations (410, 420 and 430) transmitting at least a corresponding plurality of pilot signals. A mobile station (401) in a coverage area of the system (400) receives at least one of the plurality of pilot signals and transmits a Pilot Strength Measurement Message that includes a Neighbor Set of a list of a plurality of candidate pilots for a and-off routine. A method and apparatus for determining the Neighbor Set includes finding a location of the mobile station (401) in the coverage area of system (400) and determining the list of plurality of candidate pilots in the Neighbor Set according to the location of the mobile station (401).

Abstract: 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.

Abstract: In a cellular communications system having synchronized base stations and unsynchronized base stations, wherein the synchronized base stations are synchronized to system time and have a common pilot PN sequence used for all synchronized pilot channels, a marker sequence is selected. The selected marker sequence is comprised of an M-chip portion of the common pilot PN sequence. Next, a coded portion of an unsynchronized pilot PN sequence is generated wherein the coded portion identifies a selected unsynchronized base station. The marker sequence and the coded portion of the unsynchronized pilot PN sequence are combined to form the unsynchronized pilot PN sequence that is different from the common pilot PN sequence. Thereafter, an unsynchronized pilot channel baseband signal of an unsynchronized base station is spread with the unsynchronized pilot PN sequence to produce the unsynchronized pilot channel.

Abstract: In a transceiver in a wireless communications system, data is transmitted from the transceiver to subscriber units, wherein each subscriber unit has a requested transmit power and an allocated transmit power, and wherein the allocated transmit power is based upon the requested transmit power. A request for an additional power allocation is detected, wherein such additional allocation causes a total requested power to exceed a maximum transceiver power. In response, allocated transmit power is limited for a minimum number of selected subscriber units needed to reduce a total transceiver transmit power below the maximum transceiver power.

Abstract: A communication system provides wireless communication in a coverage area and includes a base station (100) and a mobile station (290). The base station (100) has a plurality of sectors (210, 220, 230, 240, 250, 260) where a corresponding plurality of pilot signals (212, 222, 232, 242, 252, 262) are transmitted. A sector (210) transmits a forward link signal (211) for communicating to the mobile station (290). The mobile station (290) transmits a reverse link signal (215) and a message signal including a list of a plurality of candidate sectors for a soft hand-off routine. A method and apparatus of determining the candidate list includes measuring reverse link signal (215) which are received at said plurality of sectors. Then, comparing reverse link signal level received at sector (210) to the reverse link signal levels received at all other sectors of said plurality of sectors (210, 220, 230, 240, 250, 260).

Abstract: In a wireless communication system using a power control command to control power of a transmitted traffic channel (58), a signal from a transmitter (64) is received (104) via a channel. A channel quality is measured (70, 108) using the signal from the transmitter. In response to the measured channel quality (70) exceeding (80, 110) a channel quality threshold (82), a decrease traffic channel power command is sent (112) to the transmitter, and a channel quality threshold is increased (114). In response to the channel quality threshold (82) exceeding (80, 110) the measured channel quality (70), an increase traffic channel power command is sent (116) to the transmitter, and the channel quality threshold is decreased (118). A traffic signal quality may be measured (72) and compared (88) to a traffic signal quality threshold (86). The result of the comparison (132) may be used to adjust (134) the channel quality threshold (82).

Abstract: The apparatus includes a demodulator (70) responsive to a first received symbol (68) associated with a first transmitted symbol (39). The demodulator has a plurality of outputs (72) and produces a first set of outputs (99). The demodulator (70) is also responsive to a second received symbol (68) associated with a second transmitted symbol (39), and produces a second set of outputs (99). A coherent detector (100) receives some outputs from the first set of outputs (99), producing an estimate of the first transmitted symbol. The coherent detector also receives some outputs from the second set of outputs (99), producing an estimate of the second transmitted symbol. A first energy value (135) and an index (101) are associated with the first estimate, while a second energy value (135) is associated with the second estimate.

Abstract: A transmitter transmits the desired signal using a continuous duty cycle at transmission rates of less than full rate (FIG. 6 ). The energy used in each power control group is related to the transmission rate. By repeating the power control groups, time division diversity (FIG. 6 ) is provided. In the receiver, the received power control groups are analyzed and compared to several levels of energy thresholds (73, 75, 77, 79). The results of the comparisons are converted into a power control signal (74, 76, 78, 80, 81) and returned to the mobile. The mobiles are capable of selecting the appropriate bit (93) and adjusting their power (94). Alternatively, an indicator of the transmission rate can be forwarded (155) in advance of the frame. The receiver compares a power estimate with the threshold for the transmission rate indicated (166).

Abstract: In a frequency hopping cellular communication system (40) having a number of base sites (41-48) and using mobile assisted handoff, a method is offered of providing base site identification signals. The method includes the steps of assigning each base site of the number of base sites to a slot of a intersite control frame; and, periodically transmitting, in the assigned slot of the intersite control frame, the identification signal of the base site.

Abstract: A method and apparatus for digital automatic frequency control includes circuitry for frequency controlling a first information portion of a digital input signal, correlating the output with a known characteristic of the first information portion, and outputting a timing signal and channel estimation signal. The digital input signal is also decimated using the timing signal and frequency controlled into a frequency controlled output signal. This signal is used, along with a signal quality estimate derived from the channel estimation signal and first information portion, to determine an estimated frequency correction signal. The estimated frequency correction signal is used to control the frequency correction steps.

Abstract: Each of a plurality of transmitters (31-37) transmits (62) one of a plurality of known signals. The known signals being known to a receiver (40). The receiver (40) then measures the known signals (63); and using those measurements, estimates the plurality of channel responses (64). The channel responses are then used to determine a power ratio parameter (65) and a phase correction parameter (66).

Abstract: Transmission of candidate-sector signalling channels are synchronized to facilitate mobile-assisted handoff (MAHO) measurements by a mobile (125). Transmitters in candidate sectors each transmit their signalling channel at distinct frequencies and at predetermined intervals. The transmission of each signalling channel by each candidate sector transmitter is synchronized to provide a known reference to the mobile (125). When instructed, the mobile (125) need only to perform MAHO measurements at the predetermined intervals in the order and at the frequency instructed.

Abstract: A communication system utilizes rotated bursts of voice channels to implement mobile assisted handoff (MAHO). Mobile stations measure the voice channels of adjacent cells as hopping frequencies are rotated from frame-to-frame of the communication system. Measurement of the voice channels of adjacent cells can be performed by mobile stations during timeslots subsequent to their receive and transmission so that measurement during a timeslot dedicated to a control channel related to the adjacent cells is not necessary.

Abstract: A method is provided of discerning a signal of a desired user on a channel having a desired user and a plurality of interfering users, each, upon occasion, transmitting an identifiable, known pilot symbol. The method includes the steps of determining a channel response of the desired user and each of the interfering users and calculating a metric equal to the squared difference between a received signal and a sum of the products of transmitted signals and channel responses for the desired user and each of the plurality of interfering users. The method also includes the step of discerning the signal of the desired user based, at least in part, upon a minimum metric.

Abstract: In a time division multiple access (TDMA) system (10), a method (50, 60) of recovering a data signal of a transmission burst commences by obtaining the frequency transmission codes for the transmitters to be monitored (52, 62). The data signal is then received in separate transmission bursts from a first transmitter in a first time period (53, 65) and from a second transmitter in a second time period (56, 65). The data signal of one of the received transmission bursts is then selected or a plurality of the data signals are combined (58, 69) to be used by the receiver as the received data signal.