Abstract: A loopback processing method includes detecting a loopback at a first entity in a wide area network. The detection is accomplished by recognizing that a “memorized” frame has returned on the same communications interface within a given period of time. The time interval between sending the frame and detecting it returning at the same port may be recorded and sent to an operator to provide information on the relative location of the loopback in the network. A loopback detect sequence is sent from the first entity to a second entity on the communications interface in loopback. Because of the loopback, both entities receive the loopback detect sequence.

Abstract: A method and apparatus for optimizing system parameters in a cellular communication network. Pilot strength measurement messages (PSMMs) that are received by bases stations of the network to be optimized are saved in a database. The database accumulates the raw data contained in the pilot strength measurement messages. After a sufficient amount of data has been collected, a report generator compiles a statistics report for each base station based on the raw PSMM data. The present invention then provides a method for applying the information in the report in order to optimize the network parameters of the cellular system. The neighbor list which is transmitted on the paging or traffic channel is revised in accordance with the compiled statistics. The antenna tilt of the base stations is adjusted in accordance with the compiled statistics.

Abstract: An apparatus and method of providing a reliable method of entering command mode and executing modem commands with a modem comprising a wireless communications channel. A wireless communications channel inserted into a standard modem configuration splits the functions of the modem between a mobile unit and a base station. When the system enters command mode, only the base station equipment changes state. The mobile unit continues to operate in the same manner as when the system is in data mode. Any command issued in command mode requiring action from the mobile unit is first sent to the base station. The base station recognizes that the command is intended for the mobile unit and sends a mobile unit-command over an independent private command channel to the mobile unit. The mobile unit constantly monitors the private channel regardless of the state of the system.

Abstract: A loopback processing method includes detecting a loopback at a first entity in a wide area network. The detection is accomplished by recognizing that a “memorized” frame has returned on the same communications interface within a given period of time. The time interval between sending the frame and detecting it returning at the same port may be recorded and sent to an operator to provide information on the relative location of the loopback in the network. A loopback detect sequence is sent from the first entity to a second entity on the communications interface in loopback. Because of the loopback, both entities receive the loopback detect sequence. Either or both entities may inform a network operator of the loopback. The first entity has stopped using the link in loopback for real data, instead sending the loopback detect sequence. The second entity, upon detecting the loopback detect sequence, also stops using the link for real data.

Abstract: A method and apparatus for performing inter-system hard handoff between communication systems or inter-frequency hard handoff within a CDMA communication system is disclosed. The purpose is to reduce the probability of dropped calls during inter-system hard handoff. In the event that a hard handoff attempt is unsuccessful, the mobile station will return to the original system with information which the communication system of the present invention uses to assist in the performance of future handoff attempts. Alternatively, with no handoff attempt made, the mobile station monitors the destination system then returns to the original system with information used to assist in subsequent handoff attempts. The information returned from monitoring a CDMA system consists of results of a search for one or more pilots given at offsets in a specific list provided to the mobile station by the base station or a set of offsets based upon a predetermined search algorithm.

Abstract: An improved method and apparatus for using parallel amplifiers to efficiently amplify an information signal are disclosed. The improved apparatus utilizes digital signal manipulation techniques in optimizing the phase of the upconverted input signals provided to each of the parallel amplifiers. The phase and amplitude of the input signals are adjusted such that the power measured at the output of a combiner is maximized as compared to the sum of the power of combiner input signals.

Abstract: A method and apparatus for sharing antennas between bases stations that is non-band limiting. A transmit signal is received at a first port coupled to a base station. The transmit signal travels from the first port through a plurality of circulators prior to being transmitted by an antenna. A received signal is received at a second port that is communicatively coupled to the antenna. The received signal conceptually travels through the apparatus in a reverse direction to the transmit signal, through at least one of the circulator units, and is admitted to the base station using at least the same port that received the transmit signal. The signal may be split, and also received by a different base station.

Abstract: A method and system for communicating a frame of information according to both a continuous transmit format and a discontinuous transmit format. The present invention contemplates transmitting one or more data rates in either a continuous transmit mode (814) or a discontinuous transmit mode (812). The present invention contemplates continuous transmission only for certain data rates, and selection between continuous and discontinuous transmission for other data rates (810). Frames transmitted in the discontinuous transmit mode may be transmitted at a higher transmit power than in the continuous transmit mode (820). In one embodiment, the information is transmitted at a fifty-percent duty cycle during the second half of the frame when in the discontinuous transmit mode (808). During periods of non-transmission, an alternative system may be searched for as a possible candidate for hard handoff (816).

Abstract: The present invention is a novel and improved method and apparatus for reducing peak to average ratio in a system using auxiliary pilot channels as described in the TIA/EIA TR45.5 “cdma2000 ITU-R RTT Candidate Submission” to the ITU for consideration in the third generation wireless communication systems. A first method proposed in the present invention to deal with the above stated problem is to alter the phase of the auxiliary pilot channels to reduce to prevent the auxiliary pilot channels from adding constructively. A second method proposed in the present invention to deal with the above stated problem is to gate out the portion of the auxiliary pilot channels that add constructively. The present invention also proposes a novel demodulator design for receiving signals using the modified auxiliary pilot signals.

Abstract: A system and method for communicating information signals using spread spectrum communication techniques. PN sequences are constructed that provide orthogonality between the users so that mutual interference will be reduced, allowing higher capacity and better link performance. With orthogonal PN codes, the cross-correlation is zero over a predetermined time interval, resulting in no interference between the orthogonal codes, provided only that the code time frames are time aligned; with each other. In an exemplary embodiment, signals are communicated between a cell-site and mobile units using direct sequence spread spectrum communication signals. In the cell-to-mobile link, pilot, sync, paging and voice channels are defined. Information communicated on the cell-to-mobile link channels are, in general, encoded, interleaved, bi-phase shift key (BPSK) modulated with orthogonal covering of each BPSK symbol along with quadrature phase shift key (QPSK) spreading of the covered symbols.

Abstract: The invention is a CDMA transmission control technology that includes various combinations of the following functionality: decresting, in-band to out-of-band ratio (RIO), power control, and spectral shaping. Decresting reduces peaks in the CDMA signal. RIO generates a ratio based on the signal strength of in-band versus out-of-band portions of the CDMA signal. Power control adjusts the gain of the CDMA signal based on quadrature signal calculations. Spectral shaping attenuates in-band portions of the CDMA signal adjacent to the corner frequencies. The CDMA transmission control technology can be implemented in a CDMA base station to extend range and capacity.

Abstract: Apparatus for a transmitter and a receiver which enhance the performance of a system coherent demodulation by utilizing non-pilot sub-channels to enhance the accuracy of estimates of amplitude and phase noise inherent in the transmission channel is described. This enhancement is accomplished by utilizing the corrected received data on a fundamental channel to enhance a pilot channel estimate, which is subsequently utilized by a dot product module in demodulating a supplementary data channel.

Abstract: A system and method for communicating information signals using spread spectrum communication techniques. PN sequences are constructed that provide orthogonality between the users so that mutual interference will be reduced, allowing higher capacity and better link performance. With orthogonal PN codes, the cross-correlation is zero over a predetermined time interval, resulting in no interference between the orthogonal codes, provided only that the code time frames are time aligned with each other. In an exemplary embodiment, signals are communicated between a cell-site and mobile units using direct sequence spread spectrum communication signals. In the cell-to-mobile link, pilot, sync, paging and voice channels are defined. Information communicated on the cell-to-mobile link channels are, in general, encoded, interleaved, bi-phase shift key (BPSK) modulated with orthogonal covering of each BPSK symbol along with quadrature phase shift key (QPSK) spreading of the covered symbols.

Abstract: A base station and receiver system for use in a base station which achieves enhanced dependability by logically separating the diversity reception paths into different failure paths. In one embodiment, the receiver system includes a first diversity reception path for receiving a first radio signal and a second diversity reception path for receiving a second radio signal. The first and second radio signals may be amplitude and phase shifted versions of the same information signal according to well known principles of diversity reception. At least one demodulator diversity combines the first and second radio signals and demodulates the diversity combined first and second radio signals. Additionally, the first and second diversity paths are logically separated into different failure paths.

Abstract: A base station architecture splits modem functionality into modulator and demodulator entities, each configured to handle multiple telephone calls. A high-speed digital bus with associated routing elements connects multiple-channel (i.e., multiuser) modulator and demodulator elements. The modulator and demodulator elements may be physically separated, residing on different cards, and even different shelves, within the base station. During softer handoff between forward channels of the base station, multiple modulator elements use the address of a demodulator element in communication with a mobile subscriber unit. A base station controller broadcasts forward-link frames to all modulator elements. The multiple modulator elements simultaneously receive forward-link frames from the base station controller. The multiple modulator elements filter these forward-link frames and accept only those to be transmitted to the particular mobile subscriber unit in communication with the demodulator element.

Abstract: The invention is a CDMA decresting technology that reduces or eliminates peaks in the CDMA signal. The CDMA technology generates a correction signal in response to peaks in the CDMA signal that exceed a value. The value typically corresponds to the maximum power level of a power amplifier. The CDMA technology combines the correction signal with the CDMA signal to generate a decrested CDMA signal with reduced peaks. In some examples of the invention, the CDMA technology processes polar coordinate representations of the quadrature components of the CDMA signal to generate the correction signal. Using the invention, the power amplifier in a CDMA base station can operate at increased power levels without exceeding out-of-band signal power limitations. As a result, the base station operates more efficiently and with a greater range or capacity.

Abstract: The system monitors traffic on a CDMA repeater. The system receives a metric related to the operation of the CDMA repeater and automatically determines the amount of call traffic on the CDMA repeater based on the metric. The metric related to operation of the CDMA repeater could be the signal power from the CDMA repeater. The amount of the call traffic on the CDMA repeater could be measured by determining the number of users on the CDMA repeater. The number of users could be determined from a formula where the signal output is proportional to the number of users on the CDMA repeater. The system may also store or transmit to a remote location the metric or the amount of call traffic on the CDMA repeater.

Abstract: A wireless communication device automatically and seamlessly switches to an alternate, available system when it is unable to complete a call origination attempt, without requiring the user to take any affirmative actions to select the alternate system. The wireless communication device stores a list of preferred communication systems. The mobile station attempts to acquire one of these preferred communication systems upon failure of the reverse link. If that is not successful, the mobile station attempts to acquire a communication system most likely to provide service. If that is also not successful, the mobile station re-attempts acquisition of the current communication system. The mobile station also re-attempts acquisition with one of the preferred communication systems after a predetermined idle time.

Abstract: A communication device including a power key located on an outer surface of the housing which may provide multiple functions, but is resistant to initiation of undesired handset functions. Control circuitry within the communication device may be configured to ignore any actuation of the power key with a duration less than a determined time period. The control circuitry performs a first function if the power key is depressed for a first duration, and performs a second function when the power key is depressed for a second duration. For example, depression of the power key for a short period of time may silence and incoming call alert, whereas depression of the power key for a longer period of time will turn the communication device on or off.

Abstract: The invention is a CDMA spectral shaping technology that attenuates the out-of-band signal power in the CDMA signal. The in-band CDMA signal is attenuated near the corner frequencies to reduce components that provide a disproportionate contribution to the out-of-band signal power. The power amplifier in the CDMA base station can then operate at higher power levels without exceeding out-of-band signal power limitations. As a result, the power amplifier operates more efficiently and extends the range or capacity of the base station. In some examples of the invention, spectral shaping digital filters are placed between the cell site modem and the digital-to-analog converter in the base station. In other examples of the invention, spectral shaping analog filters are placed between the digital-to-analog converter and the low-pass filter in the base station.