Abstract: Because prior-art rate determination algorithms are prone to falsing, a sub-rate discrimination metric generator (160) is provided herein. The generator (160) correlates a received frame with known characteristics of sub-rate frames to generate additional metrics useful in rate determination. These metrics are passed to a modified rate determination algorithm (150).

Abstract: During operation a transmitter and receiver of a central site termination unit (TU-C) (101) are driven by a sample clock derived from a network clock source (103). A remote termination unit (TU-R) (102) operates with a free running sampling clock and acquires and tracks the network clock (103) from a downstream signal (104). The regenerated network clock is then used to drive both the receiver (107) and the transmitter (108) of the TU-R (102). In particular, the transmit samples are generated on a block by block basis using fast algorithms. To avoid glitches during data transmission caused by block processing, the data sample at the boundary of blocks of data is replaced by an interpolated value. In particular, a first order approximation to the correct value of the boundary sample is made, and the first order approximation is substituted in place of the boundary data sample of the block.

Abstract: A remote unit's (113) volume level is controlled locally through a user interface (105). The user interface (105) converts volume-up and volume-down instructions to an appropriate volume-up or volume-down command signal which is passed through a controller (107) to a local amplifier (111). When the local amplifier (111) is operating at a maximum gain level, and a user still perceives the audio output as being inadequate, an increase in volume results in the controller (107) sending a volume-up message via transmit circuitry (103) to infrastructure equipment (115). Upon receiving the volume-up message an amplifier (125) existing within the infrastructure equipment (115) increases its gain.

Abstract: A first group of bits (100, 102, 106), e.g., header symbols/bits, are interleaved to form a first group of interleaved bits. A second group of bits (104), e.g., data symbols/bits, are interleaved to form a second group of interleaved bits. The first and second groups of interleaved bits are mapped to an information burst (114). The first and second groups of interleaved bits may be mapped to the information burst relative to a group of known symbols (116) forming a training sequence. A disadvantaged bit location, i.e., a bit location within the mapping having a relative high probability of incurring a bit error, is identified and an advantaged bit location, i.e., a bit location within the mapping having a relatively low probability of incurring a bit error, is identified.

Abstract: Embedded electronics (102) are operated under normal operating conditions, with power being supplied to embedded electronics via a power source (205). Heat is generated via the normal operation of the embedded electronics (102), and a voltage (117) is generated via thermionic emission from the heat. The voltage (117) that is generated is supplied to the power source (205) to help power the embedded electronics (102).

Abstract: A method for determining a fading correction factor to be used for correcting a sample of a power delay profile of a received signal in a communication system, the fading correction factor associated with a fading channel characteristic through which the received signal propagates, includes estimating a number (N) of complex samples, obtaining fading channel autocorrelation sequence (R(n)) of the fading channel for a plurality (n) of complex samples, the number of the plurality (n) of complex samples corresponding to the number (N) of complex samples, and computing the fading correction factor based on the number (N) of complex samples, autocorrelation sequence (R(n)), and the number of the plurality (n) of complex samples.

Abstract: An improved cooling fan (12) fan for cooling an electronic component includes a rotor (26) rotatably mounted in a housing (18) and having a plurality of fan blades (28). The housing (18) includes a first end (20), a second end (24), and a passage (24) interconnecting the first end and the second end to define an air flow path (25) therebetween. An entry port (16) is defined by an upstream portion of the housing (18) generally adjacent the housing first end (20), with the entry port (16) having a cross-sectional area greater than a cross-sectional area of the passage (24). The entry port (16) and the passage (24) being separated by a transition zone (30), with the entry port (16) and the transition zone (30) cooperating to define an abrupt step (36). The abrupt step (36) is adapted to at least partially affect the flow of air flowing along the flow path (25), thereby reducing the ambient noise level of the fan.

Abstract: An apparatus (100) and method dynamically allocates radio frequency receive path resources as required by a programmable location engine (112). The programmable location engine (112) employs cascaded time of arrival and direction of arrival algorithms to determine per remote unit location data. The apparatus (100) employs a phased array antenna (104) and a programmable receiver switching apparatus (108). A plurality of radio frequency receivers (102a-102n) receive a plurality of different carriers, such as CDMA carriers, on each of a different phased array antenna element (106a-106d).

Abstract: The present invention provides a method for determining a need to retransmit a message that includes a user frame from a base station (104) in a communication system (100). A signaling message is inserted into the user frame. The user frame is transmitted from the base station (104) and received at a mobile unit (102). The mobile unit (102) transmits an erasure indicator bit to indicate that the user frame was received by the mobile unit (102). The base station (104) receives the erasure indicator bit. It is then determined, based at least in part upon the erasure indicator bit, whether the signaling message was accurately transmitted by the base station (104) and received by the mobile unit (102). If the signaling message was not accurately transmitted and received, the base station (104) will retrieve the stored signaling message and retransmit the signaling message to the mobile unit (102).

Abstract: A predistortion linear power amplifier and method employs parallel predistortion cancellation. In one embodiment the predistortion linear power amplifier (200) utilizes a signal splitter (202) to split an input carrier signal. A first amplifier, such as a main power amplifier (206) in a first path (214), receives the first split carrier signal (216). A signal predistortor (210) in a second path (218) is operatively coupled to receive a second split carrier signal (220) and to output a predistorted carrier signal (226). A second amplifier, such as a linear power amplifier (212) serially coupled with the signal predistortor (210) in the second path, amplifies the predistorted carrier signal (226). A signal combiner (208) operatively combines the output from the first amplifier and the output from the second amplifier to provide an amplified carrier output signal (230) from which nonlinear distortion has been substantially cancelled.

Abstract: A receiver (10) corrects for dynamic DC offsets by utilizing an open loop predictive DC offset correction stage (18) to respond instantly to changes in AGC settings on a timeslot by timeslot basis. The receiver has an AC coupled baseband receiver and has memory (22) for storing calibration offset data (24 and 26) representing a calibration offset voltage value for each automatic gain control (AGC) state determined relative to a known reference value. The predictive DC offset stage (18) predicts a predictive DC offset correction value (74 and 76) for a selected timeslot using stored calibration offset data (24 and 26) and an average of stored calibration offset data corresponding to AGC states for all timeslots in a given frame.

Abstract: An improved speech coder takes advantage of the fact that any given pulse combination can be uniquely described by the following four properties: number of degenerate pulses, signs of pulses, positions of pulses, and pulse magnitudes. In accordance with the invention, a four stage iterative classification of the pulse combinations, where each stage groups the pulse combinations by one of these four properties, is performed. The process starts with the number of pulses, then determines the total number of possible sign combinations, pulse position combinations, and pulse magnitude combinations. This flexibility allows for the sign combinations to be grouped in the last stage. Since the number of sign combinations is always a power of two, leaving the sign combinations for last along with appropriately ordering the elements in the previous three stages allows the signs to be coded by independent bits, in turn allowing for error protection of those bits.

Abstract: Remote units (113) having large amounts of data to transmit will be dynamically assigned Orthogonal Variable Spreading Factor (OVSF) codes corresponding to higher data rates and remote units (113) with lower amounts of data to be transmitted will be assigned OVSF codes corresponding to lower data rates. Additionally, in an alternate embodiment of the present invention, once system interference becomes greater than a predetermined threshold, the data rate between the base station (100) and remote units (113) in communication with the base station (100) is reduced. The reduction of the data rate between the base station (100) and remote units (113) occurs by changing the current OVSF codes utilized by both the remote units (113) and the base station (100).

Abstract: Frames received by base stations (base stations) (103-107) are assigned a frame-quality indicator (FQI) by the base station. FQI information for all frames received is continuously backhauled to a switch (101). The switch (101) sidehauls the FQI information to a call anchoring base station, where a determination of a base station with the best FQI for each frame takes place. Once the anchoring base station determines a base station with the best FQI for a particular frame, the anchoring base station sends a FORWARD_FRAME message to the base station with the best FQI, or, if the anchoring base station is the base station with the best FQI, nothing is sent to the other base stations. Once the FORWARD_FRAME message is received by a base station, the base station immediately forwards the frame (identified by the frame number) to the switch (101). The switch (101) then routes the selected frame accordingly.

Abstract: A mobile subscriber unit (MS) location method and system in a spread spectrum channel coding system uses a known spread spectrum location beacon channel (34) that is time division multiplexed with normal code division multiplexed channels (36). Each base station (12, 14 and 16) in a defined service area transmits the known time division multiplexed spread spectrum location beacon signal (34), such as a known location channel, as a spread spectrum location beacon signal at a same time interval. Mobile subscriber units (18) receive the spread spectrum location beacon signal (34) time division multiplexed with the normal CDMA channels (36) and determine their own location using location techniques such as trilateration. Preferably, all of a base station's transmit power is assigned to this special known location channel (34) during transmission.

Abstract: A communications operating system is provided herein. The communications operating system having a common communication system comprising a radio frequency transceiving means for transmitting and receiving radio frequency signals and a system list means for storing a list of communication systems available. The system also includes a feature list means for storing a list of feature programs, where the feature programs comprise at least one of an enabling program to enable resident functions, a high-level design specification, and an executable feature specification.

Abstract: The present invention provides a method for positioning GSM mobile stations. Positioning information for a Mobile Station (102) is requested by a Base Station Subsystem (117) from Location Determination Equipment (113). The Location Determination Equipment (113) return signal measurements relating to the Mobile Station (102) to the Base Station Subsystem (117). The Base Station Subsystem (117) requests a location calculation from a Mobile Positioning Register (111). The Mobile Positioning Register (111) computes the position of the mobile station (102) based at least in part upon the signal measurements. The position of the Mobile Station (102) is then returned to the Base Station Subsystem (117).

Abstract: A method and apparatus for estimating mobile radio channel parameters by dynamically determining the delay offset, carrier frequency offset, and coherent averaging length that yields the optimum despreading gain for current channel conditions. Obtaining the optimal despreading gain increases the fidelity of desired channel parameter estimates, (such as delay, phase, and the complex impulse response), and also expands the range of conditions under which they can be feasibly measured. A plurality of delay offsets, carrier frequency offsets, and coherent averaging lengths are considered for each measurement of channel parameters. An energy metric assigned to each combination of delay offset and coherent averaging length, and this value measures the despreading gain for these conditions.

Abstract: The present invention provides a communication system (100) and a method for determining when a communication unit (105) is located within a preferred zone in the cellular communication system (100). The cellular communication system (100) includes a plurality of cells. A preferred zone for a communication unit (100) is created. Radio characteristics associated with the preferred zone, such as pilot signal, cell ID, and distance, are obtained. It is then determined, based at least in part upon the radio characteristics, when the communication unit (100) is located within the preferred zone.

Abstract: A data transmission system identifies the length of communicated messages and adjusts interleave depth in response to the length of the communicated message. The system provides an efficient method of interleaving both voice data typically having a long message length and packet data typically having a short length.