Abstract: A method and apparatus is used for generating a perfectly random secret key between two or more transceivers in a wireless communication network. In a point-to-point system, both transceivers produce an estimate of the channel impulse response (CIR) based on the received radio signal. The CIR estimation is synchronized and may include error correction and detection. A long secret key of bits is generated from a digitized version of the CIR estimate, from which a perfectly secret encryption key is derived by privacy amplification.

Abstract: An adaptive equalizer including an equalizer filter and a tap coefficients generator used to process a sample data stream derived from a plurality of received signals is disclosed. The tap coefficients generator includes an equalizer tap update unit, a vector norm square estimator, an active taps mask generator, a switch and a pilot amplitude reference unit used to minimize the dynamic range of the equalizer filter. A dynamic mask vector is used to mask active taps generated by the equalizer tap update unit when an unmasked signal output by the equalizer filter is selected by the switch to generate an error signal fed to the equalizer tap update unit. A fixed mask vector is used to mask active taps generated by the equalizer tap update unit when a masked signal output by the equalizer filter is used to generate the error signal.

Abstract: A method and apparatus is used for generating a perfectly random secret key between two or more transceivers in a wireless communication network. In a point-to-point system, both transceivers produce an estimate of the channel impulse response (CIR) based on the received radio signal. The CIR estimation is synchronized and may include error correction and detection. A long secret key of bits is generated from a digitized version of the CIR estimate, from which a perfectly secret encryption key is derived by privacy amplification.

Abstract: A method and apparatus may be used to perform WTRU-WTRU paging in wireless communications. For example, a wireless transmit/receive unit (WTRU) may be configured to page another WTRU. In this example, the paging WTRU may receive a first message that indicates a group identification (ID). The WTRU may receive a second message that may include an indicator that indicates one or more other WTRUs that the paging WTRU may page. If the received indicator matches a paging indicator of the paging WTRU, the paging WTRU may transmit an access signal to one or more other WTRUs. The paging indicator of the paging WTRU may be predetermined, and may be received in a configuration message from a base station (BS). The first message may be a secondary advanced (SA)-preamble.

Abstract: A method and apparatus for estimating a signal-to-interference ratio (SIR) are disclosed. A received signal includes signal energy on multiple basis functions. Desired signal energy in the received signal is transformed onto a first basis function with constant polarity. The desired signal energy is estimated by coherently averaging signal energy on the first basis function. A noise power is estimated by averaging signal energy on each basis function other than the first basis function and accumulating the averaged signal energy from the basis function other than the first basis function and scaling the accumulated signal energy to account for a noise estimate from the first basis function. An SIR is estimated by dividing the desired signal energy by the noise power.

Abstract: A method and apparatus for reference transport channel (TrCH) selection includes tracking characteristics on each of a TrCH. Whether or not any TrCHs meet a predetermined criteria is determined. A reference TrCH is selected based upon the determination of TrCHs that meet the predetermined criteria.

Abstract: Detecting, avoiding and/or correcting problematic puncturing patterns in parity bit streams used when implementing punctured Turbo codes is achieved without having to avoid desirable code rates. This enables identification/avoidance of regions of relatively poor Turbo code performance. Forward error correction comprising Turbo coding and puncturing achieves a smooth functional relationship between any measure of performance and the effective coding rate resulting from combining the lower rate code generated by the Turbo encoder with puncturing of the parity bits. In one embodiment, methods to correct/avoid degradations due to Turbo coding are implemented by puncturing interactions when two or more stages of rate matching are employed.

Abstract: A method and apparatus for estimating a signal-to-interference ratio (SIR) are disclosed. A received signal includes signal energy on multiple basis functions. Desired signal energy in the received signal is transformed onto a first basis function with constant polarity. The desired signal energy is estimated by coherently averaging signal energy on the first basis function. A noise power is estimated by averaging signal energy on each basis function other than the first basis function and accumulating the averaged signal energy from the basis function other than the first basis function and scaling the accumulated signal energy to account for a noise estimate from the first basis function. An SIR is estimated by dividing the desired signal energy by the noise power.

Abstract: A method and apparatus for performing closed loop transmit power control of a fractional dedicated physical channel (F-DPCH) are disclosed. Transmit power control (TPC) symbols on an F-DPCH and common pilot channel (CPICH) symbols are received. A short term signal power estimate is calculated using the TPC symbols, and a short term noise power estimate is calculated using the CPICH symbols. A short term signal-to-interference ratio (SIR) on the F-DPCH is calculated. A long term signal power estimate and a long term noise power estimate are calculated using the TPC symbols. A long term SIR is calculated and compared to a TPC quality target. An SIR target is adjusted based on comparison of the long term SIR to the TPC quality target. The short term SIR is compared to the SIR target and a TPC command is generated based on comparison of the short term SIR to the SIR target.

Abstract: A method and system for generating a secret key from joint randomness shared by wireless transmit/receive units (WTRUs) are disclosed. A first WTRU and a second WTRU perform channel estimation to generate a sampled channel impulse response (CIR) on a channel between the first WTRU and the second WTRU. The first WTRU generates a set of bits from the sampled CIR and generates a secret key and a syndrome, (or parity bits), from the set of bits. The first WTRU sends the syndrome, (or parity bits), to the second WTRU. The second WTRU reconstructs the set of bits from the syndrome, (or parity bits), and its own sampled CIR, and generates the secret key from the reconstructed set of bits.

Abstract: Detecting, avoiding and/or correcting problematic puncturing patterns in parity bit streams used when implementing punctured Turbo codes is achieved without having to avoid desirable code rates. This enables identification/avoidance of regions of relatively poor Turbo code performance. Forward error correction comprising Turbo coding and puncturing achieves a smooth functional relationship between any measure of performance and the effective coding rate resulting from combining the lower rate code generated by the Turbo encoder with puncturing of the parity bits. In one embodiment, methods to correct/avoid degradations due to Turbo coding are implemented by puncturing interactions when two or more stages of rate matching are employed.

Abstract: The present invention is related to a method and system for preventing high speed downlink packet access (HSDPA) transmission loss due to transmission gap in compressed mode in a wireless transmit/receive unit (WTRU). In accordance with one embodiment, a Node-B receives a compressed mode transmission gap schedule of a WTRU, identifies HSDPA transmission time intervals (TTIs) that are affected by the WTRU compressed mode transmission gap schedule and schedules the HSDPA transmissions not to overlap the WTRU compressed mode transmission gap schedule. In accordance with another embodiment, the Node-B may inform the HSDPA transmission schedule to a radio network controller (RNC) and the RNC coordinates the HSDPA transmission schedule and a compressed mode transmission gap schedule of the WTRU.

Abstract: A method and apparatus for estimating attributes of a received signal that includes a plurality of transmitted signals are provided. The amplitude of the received signal is estimated by performing a method of demodulation based on known signal information. The amplitude of an M-ary quadrature amplitude modulated signal is estimated based upon known or ascertainable phase information regarding a plurality of transmitted symbols. The amplitude of a q-ary amplitude shift keyeing signal is estimated based upon known or ascertainable magnitude information regarding a plurality of transmitted symbols. Statistical information is also used for amplitude estimation.

Abstract: A method and apparatus for providing fast detection of a high speed shared control channel (HS-SCCH). The HS-SCCH carries information necessary for receiving data via a high speed downlink shared channel (HS-DSCH). The apparatus receives messages transmitted via a plurality of HS-SCCHs. The apparatus measures a channel quality for the messages received via each HS-SCCH. The apparatus performs a threshold test by comparing the channel quality with a predetermined threshold. The apparatus then selects a HS-SCCH having the best channel quality among the HS-SCCHs.

Abstract: A method and apparatus for performing closed loop transmit power control of a fractional dedicated physical channel (F-DPCH) are disclosed. Transmit power control (TPC) symbols on an F-DPCH and common pilot channel (CPICH) symbols are received. A short term signal power estimate is calculated using the TPC symbols, and a short term noise power estimate is calculated using the CPICH symbols. A short term signal-to-interference ratio (SIR) on the F-DPCH is calculated. A long term signal power estimate and a long term noise power estimate are calculated using the TPC symbols. A long term SIR is calculated and compared to a TPC quality target. An SIR target is adjusted based on comparison of the long term SIR to the TPC quality target. The short term SIR is compared to the SIR target and a TPC command is generated based on comparison of the short term SIR to the SIR target.

Abstract: An adaptive equalizer including an equalizer filter and a tap coefficients generator used to process a sample data stream derived from a plurality of received signals is disclosed. The tap coefficients generator includes an equalizer tap update unit, a vector norm square estimator, an active taps mask generator, a switch and a pilot amplitude reference unit used to minimize the dynamic range of the equalizer filter. A dynamic mask vector is used to mask active taps generated by the equalizer tap update unit when an unmasked signal output by the equalizer filter is selected by the switch to generate an error signal fed to the equalizer tap update unit. A fixed mask vector is used to mask active taps generated by the equalizer tap update unit when a masked signal output by the equalizer filter is used to generate the error signal.

Abstract: An improved receiver and method estimate one or more parameters, such as amplitude and signal-to-noise ratio, of a received signal, such as an M-QAM or q-ASK signal. The amplitude of an M-QAM signal is estimated based upon known or ascertainable phase information regarding a plurality of transmitted symbols. The amplitude of a q-ASK signal is estimated based upon known or ascertainable magnitude information regarding a plurality of transmitted symbols. In another embodiment, the amplitude of an M-QAM or q-ASK signal is estimated based on statistical knowledge of the amplitude of the transmitted symbols. Other embodiments estimate amplitude, noise power, and signal-to-noise ratio of a received signal utilizing second-order and fourth-order moments of received samples, a maximum likelihood searching process, or a Kurtosis estimation process.

Abstract: An equalization system and method which supports macro diversity as well as large delay spread channels with a minimal increase in complexity is disclosed. The equalization system includes a path searcher, an optional search scheduler, a multi-equalizer manager, an alignment buffer, a plurality of equalizers and an equalizer combiner. The path searcher detects positions of paths of the received signals. The equalizers are used to perform equalization on the received signals. The multi-equalizer manager controls the equalizers by assigning specific positions of the paths to respective ones of the equalizers. The equalizer combiner then combines outputs from the equalizers.

Abstract: A method and apparatus for estimating a signal-to-interference ratio (SIR) are disclosed. A received signal includes signal energy on multiple basis functions. Desired signal energy in the received signal is transformed onto a first basis function with constant polarity. The desired signal energy is estimated by coherently averaging signal energy on the first basis function. A noise power is estimated by averaging signal energy on each basis function other than the first basis function and accumulating the averaged signal energy from the basis function other than the first basis function and scaling the accumulated signal energy to account for a noise estimate from the first basis function. An SIR is estimated by dividing the desired signal energy by the noise power.

Abstract: An adaptive equalizer including an equalizer filter and a tap coefficients generator used to process a sample data stream derived from a plurality of received signals is disclosed. The tap coefficients generator includes an equalizer tap update unit, a vector norm square estimator, an active taps mask generator, a switch and a pilot amplitude reference unit used to minimize the dynamic range of the equalizer filter. A dynamic mask vector is used to mask active taps generated by the equalizer tap update unit when an unmasked signal output by the equalizer filter is selected by the switch to generate an error signal fed to the equalizer tap update unit. A fixed mask vector is used to mask active taps generated by the equalizer tap update unit when a masked signal output by the equalizer filter is used to generate the error signal.