摘要:
An electronic device (10). The device has means (222) for receiving SPS information from an SPS system (40). The device also comprises means (223) for receiving broadcast timing information from a source (50) other than the SPS system. The device also comprises means for determining a location fix of the electronic device in response to the SPS information and the broadcast timing information.
摘要:
A receiver (MST) for use in a modulated communications system wherein data is communicated in a time-slotted format. The receiver comprises circuitry (22) for providing samples of a group of data from the time-slotted format and circuitry (46, 42) for determining a first set of channel estimates in response to a first set of the samples. The receiver also comprises circuitry (30) for first predicting decisions for data in the group of data in response to the first set of channel estimates and circuitry (46, 42) for determining a second set of channel estimates in response to the predicted decisions. Lastly, the circuitry for predicting is further for second predicting decisions for data in the group of data in response to the second set of channel estimates.
摘要:
A system comprises a wireless device that communicates across a spectrum having a plurality of sub-channels. The wireless device comprises a plurality of antennas through which the wireless device communicates with another wireless device, wherein each antenna communicates with the other wireless device via an associated communication pathway. The wireless device further comprises sub-channel power analysis logic coupled to the antennas and adapted to determine which communication pathway has the highest communication quality on a sub-channel by sub-channel basis. The wireless device still further comprises diversity selection logic coupled to the sub-channel power analysis logic and adapted to determine a weighting vector for an associated antenna based on the communication quality, wherein the weighting vector specifies a relative transmission power for each sub-channel for the associated antenna.
摘要:
A wireless communication system (10). The system comprises a user station (12). The user station comprises despreading circuitry (22) for receiving and despreading a plurality of slots received from at least a first transmit antenna (A121) and a second transmit antenna (A122) at a transmitting station (14). Each of the plurality of slots comprises a first channel (DPCH) comprising a first set of pilot symbols and a second channel (PCCPCH) comprising a second set of pilot symbols. The user station further comprises circuitry (50) for measuring a first channel measurement (α1,n) for each given slot in the plurality of slots from the first transmit antenna and in response to the first set of pilot symbols in the given slot. The user station further comprises circuitry (50) for measuring a second channel measurement (a2,n) for each given slot in the plurality of slots from the second transmit antenna and in response to the first set of pilot symbols in the given slot. The user station further comprises circuitry (52) for measuring a phase difference value (φ2(n)) for each given slot in the plurality of slots in response to the first channel measurement and the second channel measurement for the given slot and in response to a ninety degree rotation of the given slot relative to a slot which was received by the despreading circuitry immediately preceding the given slot.
摘要:
Closed loop multiple-antenna wireless communications system with antenna weights determined by maximizing a composite channel signal-to-interference-plus-noise ratio minimum. Multiplexed symbol streams over subsets of antennas enhance throughput.
摘要:
A method for providing closed-loop transmit precoding between a transmitter and a receiver, includes defining a codebook that includes a set of unitary rotation matrices. The receiver determines which preceding rotation matrix from the codebook should be used for each sub-carrier that has been received. The receiver sends an index to the transmitter, where the transmitter reconstructs the precoding rotation matrix using the index, and precodes the symbols to be transmitted using the preceding rotation matrix. An apparatus that employs this closed-loop technique is also described.
摘要:
In a wireless MIMO system, a multimode detector selects detection mode by channel estimation: ill-conditioned channels trigger use of high performance detection, whereas well-behaved channels lead to low complexity detection. Detection modes typically include maximum likelihood, minimum mean squared error, zero forcing, and so forth.
摘要:
Method for packet transmission scheduling in a multi-carrier communications system. A preferred embodiment comprises selecting a set of users from a group of users who are targets of intended transmissions, wherein the selection is based upon channel quality information, determining a set of transmission parameters for each user in the set of users, and scheduling transmissions to the set of users. The channel quality information, which can be provided by the users of the multi-carrier communications system, can permit the exploitation of frequency diversity inherent in the multi-carrier communications system to increase system capacity to beyond a simple sum of carrier transmission bandwidth.
摘要:
Method for exploiting frequency diversity in a multi-carrier communications system to improve retransmission performance. A preferred embodiment comprises receiving the request for retransmission, formatting data for the retransmission, selecting a carrier from a plurality of carriers, and transmitting the retransmission on the selected carrier. The selected carrier may be different from a carrier used transmit the damaged transmission, thereby frequency diversity is exploited to change the probability of successful transmission in the retransmission. Alternatively, the retransmission may take place at a later time, to permit changes in the selected carrier to take place and obtain frequency diversity via the changed carrier.
摘要:
A system comprises a base station, a plurality of mobile stations, and a packet scheduling algorithm that operates on the base station. The packet scheduling algorithm groups the plurality of mobile stations into a plurality of groups based on average throughput with the base station. The packet scheduling algorithm selects one of the plurality of groups for applying a scheduling metric.