Abstract: A LINC amplifier of a radio frequency transmitter provides substantially linear amplification from two nonlinear amplifiers by decomposing the original signal into two constant amplitude envelope, phase varying signals, which, when combined, constructively and destructively interfere to re-form the original signal. The output of the LINC amplifier, which is to be transmitted via an antenna, is an amplified form of the original signal. The LINC amplifier uses a digital control mechanism to control and adapt a digital compensation network that directly compensates for the imperfections of the analog RF environment, including the amplifiers. The mechanism monitors the combined amplifier output and adjusts the signal components in order to precisely compensate for any differences in the characteristics of the separate signal paths which would cause the combination not to accurately represent the original signal.

Abstract: A LINC amplifier of a radio frequency transmitter provides substantially linear amplification from two nonlinear amplifiers by decomposing the original signal into two constant amplitude envelope, phase varying signals, which, when combined, constructively and destructively interfere to re-form the original signal. The output of the LINC amplifier, which is to be transmitted via an antenna, is an amplified form of the original signal. The LINC amplifier uses a digital control mechanism to control and adapt a digital compensation network that directly compensates for the imperfections of the analog RF environment, including the amplifiers. The mechanism monitors the combined amplifier output and adjusts the signal components in order to precisely compensate for any differences in the characteristics of the separate signal paths which would cause the combination not to accurately represent the original signal.

Abstract: Fading on a data link prevents a mobile station from acknowledging a received base station poll message. Responsive thereto, the data link is transitioned to an unacknowledged mode of operation. A group of frames of a data communication are then transmitted to the mobile station with no base station expectation of receiving a mobile station acknowledgment. Following group frame transmission, the data link is transitioned back to acknowledged mode of operation. To insure delivery of the data communication, the sent frames a queued (stored) by the base station until such time as a delivery confirmation with respect to the group of frames can be obtained.

Abstract: Methods for controlling the blocking of a network-supported primary service by a network-supported secondary service sharing the same network router/switch.A probabilistic method for resource control identifies for each secondary service connection request the likelihood that if it is allocated a network router/switch server, a subsequent primary service connection request will be blocked, i.e., denied a server allocation of its own. If it is determined that it is unlikely that allocating a secondary service connection request a server will cause a subsequent primary service connection request to be blocked, an idle server is allocated to a currently pending secondary service connection request at the router/switch.

Abstract: A Data Link is established for communicating messages between the first entity and the second entity via Information Frames communicated between a first Data Link Layer at the first entity and a second Data Link Layer at the second entity. An Information Frame addressed to the second Data Link Layer, preferably indicating a normal condition for the Data Link, is transmitted from the first Data Link Layer. The first and second Data Link Layers are reset if it is determined that a transmitted Information Frames fails to be communicated from the first Data Link Layer to the second Data Link Layer. An Information Frame addressed to the second Data Link Layer, preferably indicating a normal condition for the Data Link, is transmitted from the first Data Link Layer after the first and second Data Link Layers are reset. The Data Link preferably is maintained from the first step of transmitting through the second step of transmitting.

Abstract: A cellular communication system provides for trellis encoding/decoding of a 16 Star QAM signal. The system includes a transmitter circuit and a receiver circuit. The transmitter circuit has a Reed-Solomon encoder, an outer interleaver circuit for spreading burst errors, a cyclic trellis encoder, an inner interleaver circuit for reducing channel memory, a 16 Star QAM mapper and a radio frequency transmitter. The receiver circuit has a radio frequency receiver, equalization and filtering circuitry and timing and synchronization recovery circuitry. The receiver also has an inner deinterleaver, a trellis decoder, an outer deinterleaver, and a Reed-Solomon decoder.

Abstract: A system and method for transmitting digital data over a wireless channel uses periodically-transmitted, differentially encoded pilot words to allow a receiver to rapidly synchronize with a transmitter. Each differentially encoded pilot word comprises at least two pilot symbols that are separated by a fixed difference. The receiver monitors differences between symbols to locate the differentially encoded pilot words, and to thereby become synchronized with the transmitter. Once the receiver becomes synchronized with the transmitter, the receiver uses the pilot symbols of the differentially encoded pilot words to perform channel estimation and compensation.

Abstract: A cellular communication system provides for trellis encoding/decoding of a 16 Star QAM signal. The system includes a transmitter circuit and a receiver circuit. The transmitter circuit has a Reed-Solomon encoder, an outer interleaver circuit for spreading burst errors, a cyclic trellis encoder, an inner interleaver circuit for reducing channel memory, a 16 Star QAM mapper and a radio frequency transmitter. The receiver circuit has a radio frequency receiver, equalization and filtering circuitry and timing and synchronization recovery circuitry. The receiver also has an inner deinterleaver, a trellis decoder, an outer deinterleaver, and a Reed-Solomon decoder.

Abstract: A radio receiver's digital matched filter (52') is intended to match a pulse-shaping filter (23) in the transmitter whose signals it receives. However, the clock signal on which the matched filter's timing is based is generated by a receiver clock (58') that is independent of the transmitter clock (56) and that is subjected to no timing adjustment to bring the two clock signals into synchronism. So as to ensure that the matched and pulse-shaping filters work together as a Nyquist filter, therefore, a timing-recovery circuit (60') senses the timing offset in the matched filter's output, and a coefficient generator (80) adjusts the matched filter's coefficients in such a manner that the filter itself imposes the delay needed for the required timing relationship between the filters.