Abstract: A method and apparatus for high data rate communication in a cellular/PCS communication system is provided. Specifically, the embodiment provides for early assignment of code channel for signaling channels (F-DCCH) in soft handoff. Thus, rather than simultaneously assigning a code channel for signaling data and another for traffic data for a particular Mobile Station (MS) in soft handoff, the code channel is assigned earlier for signaling data. Some of the unnecessary Base Station (BS) procedures with respect to the signaling data may be eliminated. An embodiment includes the concept of early signaling from the MS to request a code channel for signaling data, optionally followed by signaling (at a later time) from the MS to request a code channel for traffic data. This permits the MS to have the F-DCCH in soft handoff before having the F-DTCH (Forward Dedicated Traffic Channel) in soft handoff without requiring the BS to skip any of its procedures.

Abstract: Method and apparatus for code assignments in a spread-spectrum wireless communication system incorporating a Large Area Synchronized-Code Division Multiple Access (LAS-CDMA) protocol. The method determines a set of LS codes based on an interference free window size. An arborescence structure provides the correspondence between the interference free window size and the set of LS codes. Subsets of the LS codes are formed having null cross-correlation within the interference free window. The subsets are assigned to neighboring cells in the system to reduce interference between neighbors. In one embodiment, a controller determines the subsets and makes the assignments to cells within the system.

Abstract: A method for coherent estimation of the traffic-to-pilot energy ratio is presented. A received preamble is decoded, and then re-encoded. The received preamble is then multiplied by the re-encoded preamble. The results are summed, squared, and then divided by a pilot energy value. In another method, a message carrying energy information can be inserted between a subpacket preamble and a subpacket.

Abstract: A method and apparatus which permits handoffs while the mobile station is in the system access state. This is achieved by providing for channel assignment messages to be sent over the paging channel of a plurality of base stations, which increases the probability of one of the messages getting through. In addition, this assures the mobile station will be able handoff to a different base station and have a traffic channel allocated to it on the new base station without delay. In addition, a method and apparatus which permits the mobile station to be directly assigned into a soft handoff state upon traffic channel assignment.

Abstract: A method and apparatus which permits handoffs while the mobile station is in the system access state. This is achieved by providing for channel assignment messages to be sent over the paging channel of a plurality of base stations, which increases the probability of one of the messages getting through. In addition, this assures the mobile station will be able handoff to a different base station and have a traffic channel allocated to it on the new base station without delay. In addition, a method and apparatus which permits the mobile station to be directly assigned into a soft handoff state upon traffic channel assignment.

Abstract: Techniques to enable the processing of multiple calls in a spread spectrum communications system. The call processing state machines defined by the CDMA standards (e.g., IS-95 and IS-2000) are modified to include a “traffic channel” substate indicative of the mobile station processing at least one active call. Call control (CC) state machines of various types are also provided to control the processing of the calls. To process one or more calls concurrently, a CC state machine is instantiated upon receiving an indication to process a particular call. The instantiated CC state machine is identified with, and used to control the processing of, the particular call. Upon receiving an indication to process an additional call, another CC state machine can be instantiated for the additional call. Correspondingly, upon receiving a directive to release a call, the call and its instantiated CC state machine are released.

Abstract: Collisions between messages simultaneously transmitted by multiple spread-spectrum transmitters are reduced by distributing the transmissions over the available resources of the receiver. The transmitters may be mobile stations and the receiver may be a base station in a CDMA cellular telephone system. Each mobile station uses one or more randomization methods to distribute its transmissions. In the first randomization, the mobile station time-delays its transmissions by a number of chips of the PN code with which it spreads the transmitted signal. A hash function produces the number from an identification number uniquely associated with that mobile station. In a second randomization, the mobile station randomly selects the PN code. In a third randomization, the mobile station inserts a random delay between successive message transmissions or probes if it does not receive an acknowledgement after a predetermined timeout period. A predetermined number of such transmissions is called a probe sequence.

Abstract: The present invention encompasses a mobile station comprising a transmitter for transmitting outgoing signals from the mobile station and a receiver for receiving incoming signals, the receiver coupled to the transmitter and having N subreceivers, where N is an integer greater than one and each of the N subreceivers may independently be tuned to a desired frequency.

Abstract: Controlling transmission energy in a variable rate communication system that gates out portions of a frame in a predetermined and predicable fashion. In particular, the present invention describes a method and apparatus which identifies closed loop power control commands that have been generated erroneously based on portions of a frame that have been gated. The identified power control commands are ignored. In an alternative embodiment, if identification of the erroneous power control commands occurs after response measures have been taken, the transmitting station responds by setting the transmission energy back to the state it would have been in had the erroneous power control commands been identified prior to the response.

Abstract: When insufficient traffic is present in the network to maintain synchronization in this manner, other methods must be used. One approach involves making direct measurements of the timing between base stations. This is accomplished in one of two ways. The base may interrupt its transmissions on all sectors for a short interval during which it determines the time of arrival of signals from other base stations. Given knowledge of the other base station locations, time errors relative to all other base stations may be derived. Alternatively, the base may send a short signal at high power in the mobile transmit band. This time-of-arrival of this signal is measured by the surrounding base stations and the time errors between pairs of base stations are computed. In some cases, a base station may be isolated sufficiently from all other base stations in the network such that direct base-to-base measurement is not viable.

Abstract: A mobile station transmits a plurality of channels including a pilot channel and at least one information channel. In the exemplary embodiment, the base station determines the adequacy of the transmission energy of the reverse link signal in accordance with the received energy of the reverse link pilot signal. In the present invention, the pilot channel transmission power is retained at the level it was prior to the frequency search excursion, while increasing the transmission energy of at least one other channel transmitted by the mobile station. In addition, when the mobile station is not capable of increasing the transmission energy of all of the information channels, the mobile station generates a ranking of the importance of the different information channels and selectively increases the transmission power of those channels.

Abstract: A novel and improved method for performing paging is described. In one embodiment of the invention a searcher is used to detect spread spectrum signals. Samples received RF signals are stored in a sample buffer. During standby mode, the samples are gathered during paging slots assigned to the mobile. A set of searches are performed on the samples, and if pilot signals are detected additional demodulation is performed to detect paging messages. The resulting set of demodulation data may be combined to increase detection. After a page message has been detected, additional demodulation resources may be activated to processes more complete page messages, or other information channels. In one embodiment of the invention, the searcher includes a demodulator to perform quick page detection without the use of finger elements to reduce idle mode power consumption.

Abstract: A novel and improved method for implementing a high-transmission-rate over-the-air interface is described. A transmit system provides an in-phase channel set and a quadrature-phase channel set. The in-phase channel set is used to provide a complete set of orthogonal medium rate control and traffic channels. The quadrature-phase channel set is used to provide a high-rate supplemental channel and an extended set of medium rate channels that are orthogonal to each other and the original medium rate channels. The high-rate supplemental channel is generated over a set of medium rate channels using a short channel code. The medium rate channel are generated using a set of long channel codes.

Abstract: Access to a variable rate multiple access system is controlled based upon a current loading. The current loading level is used to determine a transmission rate set point. The transmission rate set point may include a maximum transmission rate and a transmission probability. The transmission rate set point is passed to the remote unit which may access the system. A remote unit with data to send determines a desired transmission data rate. If the desire transmission data rate is equal to or greater than the maximum transmission data rate, the remote unit transmits at the maximum transmission data rate with a probability equal to the transmission probability.

Abstract: A method and apparatus for minimizing the amount of time that a mobile station is to be out of communication with an “origination” base station while searching for a suitable system to which to perform a mobile station assisted hard handoff. After being directed to search for pilot signals in an alternate frequency band, the mobile station tunes to that alternate frequency and samples the incoming data, storing those samples in memory. When a sufficient number of samples have been stored, the mobile station retunes to the origination frequency. The forward link data is again received by the mobile station, and reverse link data can be successfully transmitted to the origination base station. After retuning to the origination frequency, a searcher in the mobile station will subsequently be employed to search for pilot signal offsets utilizing the stored data collected from the alternate frequency.

Abstract: A communications network and method for over the air service programming a mobile station (2), where the mobile station transmits a service programming request to a communications network, which results in the mobile station (2) being connected to a customer service center (26). Customer service center (26) queries the user of mobile station (2) for information in response to which the customer service center (26) selects a home location register (18) and authentication center (22) within the communication network with which the mobile station (2) is to be associated. Service programming information associated with the mobile station (2) is transferred from the home location register (18) and/or the authentication center (22) into mobile station (2).

Abstract: A method and apparatus for coordinating the time at which a mobile station performs searches for alternative systems to which a hard handoff will occur. In one system which includes the present invention, the mobile station receives a command which instructs the mobile station as to when to tune to alternative frequencies in order to search for indicates of the presence of an alternative system. In another system which includes the present invention, predetermined times are defined with respect to a reference point in time that is common to both the origination base station and a mobile station. The mobile station tunes to alternative frequencies to perform searches only during these predetermined times. In addition, the mobile station coordinates the transmission of reports which indicate the results of searches for alternative systems such that these reports are only transmitted from the mobile station when the mobile station is tuned to the origination frequency.

Abstract: A novel and improved method and apparatus for generating a reduced peak amplitude high data rate channel comprised of a set of lower rate channels is described. The set of lower rate channels are phase rotated before being summed and transmitted. The amount of phase rotation is dependent on the number of channels used to form the higher rate channel. In an embodiment where two lower rate channels are used, the in-phase and quadrature-phase components of the two channels are complex multiplied before upconversion with an in-phase and quadrature-phase sinusoids. For a high rate channel comprised of more than two lower rate channels, the in-phase and quadrature-phase component of each channel is upconverted with a set of sinusoids that are phase offset from one another.

Abstract: Demodulation of a received high rate CDMA wireless signal is obtained by filtering a complex received signal to provide a complex pilot filter signal. The complex pilot filter signal is then used to phase-adjust a set of demodulated subscriber channel signals.

Abstract: A channel structure for use in communication systems. Two sets of physical channels, one for the forward link and another for the reverse link, are utilized to facilitate communication of a variety of logical channels. The physical channels comprise data and control channels. In the exemplary embodiment, the data channels comprise fundamental channels which are used to transmit voice traffic, data traffic, high speed data, and other overhead information and supplemental channels which are used to transmit high speed data. The fundamental channels can be released when the remote stations are idle to more fully utilized the available capacity. The control channels are used to transmit paging and control messages and scheduling information.