Abstract: A system, terminal, receiver and method are provided for receiving and processing a signal received from a spread-spectrum downlink channel. The method includes receiving the signal from the downlink channel, and generating an estimate of a transmitted chip sequence in accordance with an iterative process. In this regard, the iterative process includes calculating statistical information, such as a mean and covariance, for a previous iteration of a transmitted chip sequence, the statistical information being selectively calculated based upon one of soft bits and soft symbols associated with the previous iteration of the transmitted chip sequence. The estimate for a current iteration of the chip sequence is then generated based upon the statistical information.

Abstract: Receiving downlink CDMA signals in a fast-fading environment is facilitated at higher receiver velocities by updating the block-adaptive linear minimum mean square error (LMMSE) downlink CDMA equalizer. The autocorrelation matrix of the observed data is updated by passing block-wise autocorrelation slides through a filter. Each autocorrelation slide is an autocorrelation matrix estimated from a short block of observed data over which the channel can be considered constant. This method achieves a reliable estimate for the autocorrelation matrix when the block size must be small to ensure that the block-wise stationarity assumption holds in cases of fast fading channels. In addition, small block sizes make it possible to satisfy the equalizer delay constraint imposed by hardware and certain voice transmission standards such as CDMA2000 1X where demodulated data must be delivered within only several symbol periods of the signal arrival time.

Abstract: Receiving downlink CDMA signals in a fast-fading environment is facilitated at higher receiver velocities by updating the block-adaptive linear minimum mean square error (LMMSE) downlink CDMA equalizer. The autocorrelation matrix of the observed data is updated by passing block-wise autocorrelation slides through a filter. Each autocorrelation slide is an autocorrelation matrix estimated from a short block of observed data over which the channel can be considered constant. This method achieves a reliable estimate for the autocorrelation matrix when the block size must be small to ensure that the block-wise stationarity assumption holds in cases of fast fading channels. In addition, small block sizes make it possible to satisfy the equalizer delay constraint imposed by hardware and certain voice transmission standards such as CDMA2000 1× where demodulated data must be delivered within only several symbol periods of the signal arrival time.

Abstract: A system, terminal, receiver and method are provided for receiving and processing a signal received from a spread-spectrum downlink channel. The method includes receiving the signal from the downlink channel, and generating an estimate of a transmitted chip sequence in accordance with an iterative process. In this regard, the iterative process includes calculating statistical information, such as a mean and covariance, for a previous iteration of a transmitted chip sequence, the statistical information being selectively calculated based upon one of soft bits and soft symbols associated with the previous iteration of the transmitted chip sequence. The estimate for a current iteration of the chip sequence is then generated based upon the statistical information.

Abstract: Methods and apparatus that implement a transmitter unit and a control unit to alert a user if the control unit is beyond a limited range of communications. A method of alerting a user that a transmitter unit is beyond a limited range of communicating wirelessly with a control unit may include, wirelessly transmitting a radio frequency signal from the transmitter unit to the control unit, determining at the control unit whether the transmitter unit is beyond the limited range of wireless communications, and selectively generating an alert at the control unit based on a result of the determination. Determining at the control unit whether the transmitter unit is beyond the limited range of wireless communications may include detecting an occurrence of a predetermined condition.

Abstract: This invention teaches methods, and circuits that operate in accordance with the methods, for improving the management and control of pilot channel sets for a CDMA mobile station. In one aspect a Priority Neighbor Search technique is provided, wherein a list of Priority Neighbor pilot channels is maintained and searched with a higher priority than the Neighbor Set pilot channels. In a further aspect this invention provides a Dropped Pilot Channel Search technique wherein a set is made of the last pilot channel or pilot channels dropped from the Active Set, wherein the dropped pilot channels are searched for some period of time with a higher priority than the Neighbor Set pilot channels. This invention also provides a High Priority Search Set feature which includes members of the Active Set, the Candidate Set, the Dropped Pilot Set, and the Priority Neighbor Set.

Abstract: In the front end of a CDMA cellular or broadband PCS mobile phone receiver, a switched bypass connection is provided to bypass the low noise amplifier, sending the received signal through an amplifier bypass connection. The amplifier bypass connection may include an attenuator. The switched bypass is activated by a control signal generated by a digital signal processor. The digital signal processor analyzes the received signal to detect and determine the relative contribution of the IMD interference to the total received signal power and, when the IMD interference exceeds a predetermined level, sends a control signal to bypass the low noise amplifier. Identification of the presence of IMD interference is by spectral estimation to discern when the mobile phone is in the presence of large near-band signals from an AMPS or other narrow-band base station which causes in-band IMD.