Abstract: Techniques for measuring signal quality in a communications link supporting OFDM symbol transfer across plural sub-carriers are disclosed. These techniques employ a link interface receiving OFDM symbol(s) from the link, and a signal-to-noise ratio (SNR) estimation unit generating an estimate of a geometric SNR (SNRgeo) for the received symbols based on an average of the logrithmic difference between soft decision and hard decisions for the received symbol. SNRgeo here defines a scalar measure of the link signal quality, which results in a computationally efficient yet accurate link signal quality assessment, and thereby permit selective link characteristic alteration. Only sub-carrier subsets need be used to derive a relatively an accurate SNRgeo estimate. Sharing calculation resources between SNR estimation and soft decision units further reduce implementation complexity.

Abstract: A radio apparatus (95), particularly for mobile radio, which makes it possible to adjust the signal reception in a predeterminably optimized way is proposed. The radio apparatus (95) includes a receiver part (1) and an evaluation unit (5), which controls the sensitivity and/or the signal-to-noise ratio of the receiver part (1) as a function of a predeterminable signal reception quality and the actual signal reception. In the event of defective signal reception, the evaluation unit (5) increases the sensitivity and/or the signal-to-noise ratio of the receiver part (1), and when signal reception is error-free for a predeterminable time it reduces the sensitivity and/or the signal-to-noise ratio of the receiver part (1).

Abstract: Channel coding is used on the forward link of a CDMA cellular telephone network to allow the CDMA mobile channel decoder to perform error correction. On a wireless link, channel code performance is improved by providing the channel decoder with an estimate of the reliability of each received symbol. This reliability information is typically the ratio of desired signal energy to interference plus noise variance at the channel decoder input. This invention improves CDMA mobile channel decoder performance using a new technique for calculating more accurate estimates of the signal to interference plus noise ratio at the input of the mobile channel decoder.

Abstract: An antenna level display device capable of faithfully reflecting any deterioration of a picture quality in receiving a satellite broadcast. In this display device, orthogonal detection of an input signal is executed in a demodulator, and a CN ratio is calculated from a conversion table in a ROM according to the mean value of deflections of mapped points of the received signal on an IQ plane. The demodulated data is compared, in a comparator, with the demodulated data obtained after error correction by a Viterbi decoder, and a CN ratio is calculated on the basis of the bit error rate from a conversion table stored in another ROM. A decision is made to select one CN ratio, which is to be displayed as an antenna level, out of the two calculated CN ratios, and the selected CN ratio is displayed through adaptive switching.

Abstract: A system and method of reducing noise in an electronic shelf label system which shifts operation of the receiver away from noise frequencies. The system includes a controller for receiving signal levels and noise levels at different frequencies from a homodyne receiver, and for shifting operation of the receiver away from noise frequencies.

Abstract: A method for detecting a failure in a radio frequency (RF) device (200) that includes a transistor (210) having a first terminal at an RF input (220), a second terminal at an RF output (260), and a third terminal at an RF common (230). The method includes the steps of: detecting a first voltage at the first terminal; comparing the first voltage to a reference voltage; and determining whether the RF transistor (210) is operating in a normal state or a failed state as a function of whether the first voltage falls inside or outside of a predetermined threshold value of the reference voltage.

Abstract: Saturation of an RF front end in a radio receiver is prevented when receiving a desired radio broadcast signal via an antenna in the presence of a strong, undesired radio broadcast signal within a passband of the RF front end. An antenna signal from the antenna is coupled to the RF front end, thereby generating an amplified signal. The radio receiver demodulates the desired radio broadcast signal in response to the amplified signal, thereby generating a demodulated signal. A signal-to-noise quality parameter of the demodulated signal is determined. The antenna signal is attenuated prior to coupling it to the RF front end by an attenuation determined in response to the signal-to-noise quality parameter.

Abstract: A system and a method for reverse link power control in a wireless communications network generates power adjust commands for mobiles being served by a network base station in a centralized manner by considering overall system performance when an increased interference condition is detected. In one implementation, a base station power control processor adopts a modified reverse inner loop power control (RILPC) and/or a reverse outer loop power control (ROLPC) algorithm when an increased interference condition is detected. According to the modified RILPC algorithm, a percentage of power-up adjust commands which would normally be generated when Eb/No measurements for served mobiles do not meet target Eb/No levels are converted to power down-adjust commands, thereby forcing some mobiles to reduce transmit power, at least temporarily, to constrain interference. When the increased interference condition persists, the percentage of power-up adjust commands which are converted to power-down commands may be changed.

Abstract: A method in a radio communication device having a receiver receiving a wideband signal in the presence of narrowband blockers method in direct conversion and intermediate frequency RF receivers including determining power for signal distortion products (40), determining power for a desired signal and the distortion products (41), filtering the signal distortion products with a filter having a bandwidth of rejection, and dynamically adjusting a rejection property (43) as a function of the power for both the desired signal and the signal distortion products. In some embodiments, a determination is made whether a ratio of powers exceeds a threshold (45) as a condition for adjusting the rejection property.

Abstract: A method includes monitoring a variable-rate data communication channel to determine its signal-to-noise ratio, and adjusting the data transmission rate of the variable rate data communication channel based on its signal-to-noise ratio.

Abstract: A down converter using a C/N ratio correcting circuit of a base station for a mobile communication network includes: a first splitter for splitting an RF signal applied from an antenna; a VGA for controlling the gain of the RF signal split by the first splitter; a down converter for receiving the RF signal gain-compensated by the VGA and converting it to an IF signal; an amplifier for amplifying the RF signal split by the first splitter; a first voltage detect circuit for converting the RF signal applied from the amplifier to a voltage; a second voltage detect circuit for converting the IF signal fedback from the down converter to a voltage; and a comparator for comparing the voltage applied from the second voltage detect circuit and the voltage applied from the first voltage detect circuit and controlling the VGA.

Abstract: A method of remotely estimating the functionality of a preamplifier mounted adjacent an antenna at the top of a mast or tower and coupled to a base station via a transmission medium, such as a coaxial cable, includes taking noise and/or signal power measurements at the base station via the coaxial cable for the amplifier when both powered and unpowered. The ratio of the respective noise and/or signal powers, after the receiver noise figure at the base station and the cable loss (estimated or measured) including any connection device loss are accounted for, provides an estimate of the functionality of the amplifier.

Abstract: The present invention proposes a method for estimating a signal variance of a received signal (y) transmitted via a transmission channel, said method comprising the steps of: estimating the energy (RSSI) of the received signal (y), estimating the energy (Emax) of channel impulse response (h) taps, and estimating said signal variance (VAR) of said received signal by subtracting said estimated energy of channel impulse response taps (Emax) from said estimated energy (RSSI) of said received signal, such that said signal variance is obtained as VAR=RSSI?Emax. The present invention also proposes a correspondingly adapted device.

Abstract: An apparatus and method are described in which a corrected signal-to-interference ratio (SIR) is determined in a cellular telephone receiver. First the estimated signal strength at the receiver is measured, then the estimated interference level is measured. The signal strength and the interference values are separately corrected in accordance with an algorithm. Thereafter, a corrected SIR value is obtained by dividing the corrected signal strength and the corrected interference values.

Abstract: Received signal characteristics of multiple concurrently received channels are determined using an analytical approach for computation in lieu of the measurement based approach of the prior art. A receiving wireless transmit receive unit (WTRU) and method are provided for processing concurrent communication signals from a plurality of transmitting WTRUs that concurrently transmit successive data blocks in a plurality of K forward channels. The receiving WTRU preferably has a receiver configured to receive successive data blocks of K concurrent transmissions transmitted from the transmitting WTRUs on the respective K forward channels. A processor is configured to compute individual channel characteristics for each forward channel k based on the characteristics of data signals received on all K forward channel.

Abstract: A mobile communication system is composed of a plurality of base stations, a mobile terminal, and a base station controller. The base station controller selects a communication base station from among the plurality of base stations based on a velocity of the mobile terminal. The mobile terminal establishes a channel with the communication base station.

Abstract: A method and apparatus for dynamically controlling a programmable gain amplifier (PGA) to provide a plurality of gain steps thereby providing automatic gain control (AGC) in a receiver intermediate frequency (IF) stage comprising a succession of operational amplifiers wherein at least one is for providing fine gain control and wherein the gain of each fine gain amplifier is controlled by the resistance ratios of a plurality of selectively biased MOSFETs. In one embodiment of the invention, three coarse amplifiers are provided, each having a gain of either 0 dB or 12 dB based on the value of a two-state signal provided to each amplifier gain control input. A single fine gain amplifier has a gain of 0 dB, 3 dB, 6 dB or 9 dB based on the binary value of the two-bit signal provided to the amplifier. The combination of three coarse gain amplifiers and one fine gain amplifier provides for a total gain of 45 dB in 3 dB steps in the described embodiment of the invention.

Abstract: An antenna weight estimation method in a mobile communication system is capable of improving the accuracy of antenna weight estimation values, thereby improving communication quality and increasing radio channel capacity. It operates instantaneous estimation and accumulative estimation in parallel, in which the former is made for estimating the antenna weight used for received SNIR estimation for transmission power control, and the latter is made for demodulating the received data. Thus, it can obtain the antenna weight for the received SNIR measurement with a minimum delay, and at the same time, it can improve the reliability of the antenna weight for the data demodulation.

Abstract: An apparatus (135), method and computer program are provided for determining and indicating a quality of a signal received by a first wireless communication device (105) from a second wireless communication device (110). In one embodiment, the apparatus (135) includes a bit-error-rate (BER) circuit (215) for measuring a BER of the signal, a comparator (145) for comparing the BER with a predetermined value to determine a relative signal quality, and an indicator (160) for indicating the quality of the signal to a user of the first device (105). Alternatively, the apparatus (135) includes a circuit for measuring the strength of the signal (230), a calculator (235) for calculating a signal-to-noise ratio (SNR) of the signal using the strength of the signal and a predetermined noise value, and a comparator (145) for comparing the SNR with a predetermined value to determine a relative signal quality.

Abstract: Systems and methods for predicting the signal-to-interference-and-noise ratio (SINR) of the signal to be received by a mobile station transmitted from a base station in a wireless data communications system, for the purpose of forward link data rate control in the presence of partly periodic SINR fluctuations. The invention involves determination of a periodic mean SINR component in the received SINR process, and upon such determination the activation of a method which comprises a periodic mean SINR estimator, a subtractor which subtracts the periodic component from the received SINR process to produce an intermediate SINR process, a generic predictor which may be used to perform predictions on the intermediate SINR process, an adder which adds back an appropriate mean value to the intermediate SINR prediction. The resulting final SINR prediction is then used for rate selection.

Abstract: In the method for dynamically determining interference and carrier-to-interference ratio, interference is measured during an active TDMA time slot. In one embodiment, a base station determines the interference level in an active time slot using power level measurement taken during a DTX OFF period, when a mobile station is transmitting in discontinuous transmission mode. In another embodiment, a base station orders a mobile station to cease transmission during a SACCH portion of the time slot, and determines an interference level I measurement using power level measurements taken during the inactive SACCH field. Another embodiment provides for the determination of an interference level I using power level measurements taken during the guard and ramp fields.

Abstract: Estimation of a signal to interference ratio in a cellular communications system is described wherein an estimate for interference is the weighted sum of individual interference estimates along each of a plurality of multi-paths, weighted according to estimates of the signal power, likewise along each of a plurality of multi-paths.

Abstract: There is provided a radio station and a radio network controller performing communication by CDMA, able to change transmission speed in response to the propagation environment, and carry on communications without communication quality degradation. The radio station comprises a signal quality reception unit for receiving information of quality of the signals having been transmitted by the radio station, received by a party thereof, and sent to the radio station by the party, in which the information is measured from the received signals by the party, and a code multiplicity determination unit configured to determine a code multiplicity of signals transmitted from the radio station to the party based on the received information of signal quality. The radio station transmits the signals to the party using the determined code multiplicity.

Abstract: A method of combining a channel quality estimate for the radio channel based on direct measurement of carrier and interferer energies, and a channel quality estimate for the radio channel based on channel decoder metrics, to obtain a final channel quality estimate in terms of carrier-to-interference (C/I) ratio for the radio channel, which is more reliable, consistent and accurate than that obtained with the individual methods. After computing a direct channel quality estimate and a decoder metric-based channel quality estimate for the radio channel, confidence levels, P(direct), P (metric), are assigned to the two estimates. P(direct) is multiplied with the direct channel quality estimate and P(metric) is multiplied with the decoder metric channel quality estimate. The respective products are added to obtain the final channel quality estimate in terms of the carrier-to-interference (C/I) ratio for the radio channel.

Abstract: Methods, apparatus, and systems for mode assignment and mode adaptation to channel conditions are provided which are based on estimations of real signal-to-noise ratios (SNR) for each frequency carrier bearing information during a data transmission session. The invention utilizes two principal procedures: signal-to-noise ratio (SNR) estimation, and a corresponding mode assignment. SNR estimation is obtained by an averaging of squared Euclidean distances between normalized received signals and reference signals corresponding to either current hard decisions from the output of a demodulator or soft decisions provided by a decoder, for each frequency carrier bearing random information. Using the SNR estimations, various algorithms for determining mode assignment are provided.

Abstract: Apparatus, and an associated method, for adaptively controlling filter characteristics of a filter forming part of a receive station, such as a mobile station operable in a cellular communication system. An adaptive parameter unit is provided with signal representations of signals that are to be applied to the filter element. The adaptive parameter unit, responsive to measurement or other analysis of the signal indicia, selects the filter characteristics to be exhibited by the filter. And, the filter characteristics are caused to be selected responsive thereto. Dynamic selection and reselection of the filter characteristics is effectuated in which the response time of the filter is minimized during good signal conditions and increased, to permit increased filter operations, during weak signal conditions.

Abstract: A picture quality measurement technique using blockiness provides realtime analysis without the use of a reference signal. A field/frame of an image represented by a processed video signal is captured in a bit-map for analysis. The image is filtered to enhance edges and then correlated with a kernel having a size corresponding to the block size of the compression algorithm used in compressing and decompressing the video signal to produce the processed video signal. The correlation results are processed by comparing an average value with the maximum value to produce a picture quality rating for the processed video signal.

Abstract: An apparatus and method are described for producing a test signal with a desired signal-to-noise ratio on a selectable output frequency for measuring a transmission system. A carrier signal, generated from a carrier signal, and a noise signal are remixed with the carrier signal in a bandwidth equal to or smaller than a smallest signal bandwidth of the transmission system. The levels of the carrier signal and the noise signal are adjusted to a predetermined ratio based on a measurement of the remixed carrier signal and the remixed noise signal. The noise signal is attenuated and added to the carrier signal until the desired signal-to-noise ratio is attained.

Abstract: A base station controller and method for controlling a forward link power level in a CDMA cellular system provides an adjustment threshold. The method includes the steps of defining the adjustment threshold for the forward link power level, and receiving an inner-loop power control command from a remote transmitter. The power control command defines a request for an incremental adjustment in the forward link power level. The method further provides for defining the forward link power level based on the adjustment threshold and the request. Tracking a cumulative power adjustment of the forward link power level allows the base station controller to avoid continuous increases in transmitted power when the power commands are actually the result of multipath effects. The result is an improvement in overall cell operation.

Abstract: Techniques to determine whether or not a terminal is under the coverage of a current wireless communication system (e.g., a packet data system) and to switch from the current system to another wireless communication system (e.g., a voice/data system). In one method, at least one measurement of at least one parameter for at least one base station in the current system is initially obtained. The measurement(s) may be SNR measurements. A metric is derived based on the measurement(s) and used (typically along with a metric threshold and a timer) to determine whether or not the terminal is within the coverage of the current system. A switch to another system is initiated if the terminal is deemed to be outside the coverage of the current system. The two systems provide at least one common service (e.g., packet data service).

Abstract: A power control device and method in a mobile communication system. Upon receipt of a call request, a base station selects a call type corresponding to the call request. The base station includes a memory for storing power control parameter values for every call type serviceable in the mobile communication system. The base station reads a power control parameter value corresponding to the selected call type from the memory, and provides the read power control parameter value to the mobile station to perform outer loop power control.

Abstract: An adaptive weighted parallel interference cancellation system for CDMA that decreases MAI (multiple access interference) and thereby increases general performance, including K stages for iterative cancellation of MAI in a received signal of a user. Each stage includes a detector, a regenerator, and a subtractor. The detector is configured to determine a tentative bit decision from a despread signal. The regenerator that is connected with the detector in parallel is configured to spread an unmodulated signal, multiply a channel phase, and multiply by the output of the detector. The subtractor uses weighted signals that are adjusted user by user and according to changing environments.

Abstract: The noise in a frequency demodulated audio signal is detected on the basis of the characteristics of the stereo-multiplex signal to obtain a very reliable information that can be used for the sliding stereo-mono transition, noise blanking and a de-noising of the stereo difference signal. A noise (vd,q(t)) is calculated by performing a coherent amplitude demodulation of the frequency demodulated stereo-multiplex signal with the second harmonic of the pilot carrier that is quadrature to the pilot carrier and as a direct measure for the quality of the signal generating the variance (&sgr;2vd,q) of the noise signal by squaring and thereafter averaging the noise signal.

Abstract: A method for decreasing upward-joining-noise in an upward-signal-inputting position of a center device includes the steps of: measuring a noise level of each of a plurality of upward signals supplied from a plurality of transmission lines; determining whether the measured noise level of each upward signal is low enough or not; and based on a determination result, controlling and adjusting a level of each upward signal. Therefore, the level of an upward signal, for which the noise level of the upward signal is determined to be low enough, is adjusted higher but still kept at a level low enough not to interfere with upward signals from other transmission lines.

Abstract: Systems and methods for predicting the signal-to-interference-and-noise ratio (SINR) of the signal to be received by a mobile station transmitted from a base station in a wireless data communications system, for the purpose of forward link data rate control in the presence of partly periodic SINR fluctuations. The invention involves determination of a periodic mean SINR component in the received SINR process, and upon such determination the activation of a method which comprises a periodic mean SINR estimator, a subtractor which subtracts the periodic component from the received SINR process to produce an intermediate SINR process, a generic predictor which may be used to perform predictions on the intermediate SINR process, an adder which adds back an appropriate mean value to the intermediate SINR prediction. The resulting final SINR prediction is then used for rate selection.

Abstract: The present invention provides methods and apparatus for controlling power utilization in a wireless communication receiver. A representative system comprises a signal properties evaluation module, an analog to digital converter (ADC), and an analog to digital converter control module. The signal properties evaluation module evaluates the stability of a received signal, and provides an indication of the stability. The ADC control module responds to the signal properties evaluation module to select the precision of the ADC based upon the indication of the stability. The ADC has at least two modes of operation, comprising a first precision and a second precision, and is responsive to the signal properties evaluation module to operate in at least one of two modes based upon the stability. The ADC responds to the signal properties evaluation module so as to limit the amount of power consumed by the wireless communications device.

Abstract: A radio communication apparatus subjects each signal which is received via a multi-path and demodulated, to a Hadamard transform at each of fingers, by use of an M-ary quadrature coding scheme, obtains correlation values of codes, combines correlation values output from fingers which obtain valid correlation values, and demodulates a received signal based on a maximum correlation value of combined correlation values. The radio communication apparatus includes an operation unit which obtains a difference between a maximum value and a second largest value of the correlation values of a corresponding one of the fingers, and a lock controller which enables and locks the correlation values output from the corresponding one of the fingers when the difference obtained by the operation unit is greater than or equal to a predetermined value.

Abstract: An apparatus for use in a receiver in a communication system in which signals cover a wide range of power levels. The apparatus provides reduced power consumption without sacrificing receiver sensitivity by using an amplifier having a fixed, relatively narrow dynamic range that can by selectively positioned to accommodate the wide range of power levels. The amplifier is placed earlier in the receiver signal processing chain than comparable amplifiers in conventional receivers.

Abstract: A multi-sensor data fusion system and method provides adaptive weighting of the contributions from a plurality of sensors in the system using an additive calculation of a sensor reliability function for each sensor. During a predetermined tracking period, data is received from each individual sensor in the system and a sensor reliability function is determined for each sensor based on the SNR (signal-to-noise ratio) for the received data from each sensor. Each sensor reliability function is individually weighted based on the SNR for each sensor and a comparison of predetermined sensor operation characteristics for each sensor and a best performing (most reliable) sensor. Additive calculations are performed on the sensor reliability functions to produce both an absolute and a relative reliability function which provide a confidence level for the multi-sensor system relating to the correct classification (recognition) of targets and decoys.

Abstract: SIR (signal to impairment power ratio) of a received signal in a communications system is determined from DC components produced by at least two successive stages of performing a non-linear operation, e.g., squaring, the signal and separating the DC component from a non-DC component for supply to the next stage. A signal power of a desired signal component of the received signal can also be determined from the DC components. The signal power can be auto-correlated, and normalized auto-correlation results which exceed a threshold can be used to determine a Doppler bandwidth of the received signal, which can be used to adaptively adjust filters used for separating the DC components.

Abstract: The invention relates to a method for load control and a radio system. In the invention a load result describing the load is cell-specifically formed. The load result is formed either by comparing a signal strength of desired signals and a combined total strength of interferences and the desired signals or by weighting a signal-to-interference ratio with a bandwidth or a data transmission rate. The load result is compared with a threshold value of the highest load level allowed of a cell. The data transmission rate in the cell is increased if the load result is smaller than the threshold value. The data transmission rate in the cell is reduced and the establishment of new connections is avoided if the load result exceeds the threshold value. In heavy load situations a signal-to-interference objective is also changed in order to balance the load result.

Abstract: A method of performing power control in a mobile communication system is disclosed. In the method, power control information is transmitted to a terminal by using a terminal power control threshold of the terminal being changed in due consideration of a communication circumstance in case of that a high-speed data transmission terminal is scheduled during receiving low-speed and voice data from the terminal.

Abstract: Variations in received signal amplitude caused by filter characteristics are reduced by a C/I measuring apparatus for a signal having a fluctuating carrier-frequency, comprising a filter for filtering the signal and means for splitting the signal into an RSS signal representing the signal strength and a BB signal representing the momentary carrier frequency deviation, comprising means for measuring the RSS signal unaffected by the frequency dependent attenuation in the IF filter. A method of measuring the C/I of a received signal is also disclosed. The method comprises the steps of filtering the signal using an IF filter to obtain one signal channel, feeding the signal to the FM detector and the RSSI unit, and measuring the signal strength of the received signal at a selected, substantially constant, carrier frequency.

Abstract: In a radio communication system comprising a primary station (100) and a secondary station (110), the primary station is able to employ one of a plurality of transmission schemes for transmissions to the secondary station. The secondary station determines a quality parameter relating to a downlink channel (122) and from this parameter determines a measurement report to signal to the primary station. The measurement report indicates a suitable transmission power for one transmission scheme, and the primary station is able to determine from a plurality of power offsets between transmission schemes respective transmission powers for a plurality of transmission schemes. The power offsets may be signalled to the primary station by the secondary station. Such a scheme provides sufficient flexibility to handle a wide range of receiver capabilities without the need for excessive signalling.

Abstract: A radio system (10) and radio system (1, 2) in which the value of parameters for a model of a received multipath signal transmitted by a remote station (20) are estimated. A sounding signal transmitted and received by the radio station is used to derive data about the reflecting environment and this data is incorporated into the model after scaling it to represent the multipath signal received from a remote station. Optionally or alternatively the remote station may transmit a sounding signal and derive data about its reflecting environment and transmit this data to the radio station, The model may incorporate both sets of derived data, particularly if they are uncorrelated. The values of the resulting parameters are exploited in applications such as ranging, location or equalisation.

Abstract: The present invention is a system for increasing Signal-to-Noise Ratio (SNR) in a wireless communication system comprising a plurality of antennas each antenna providing a signal, a device for selecting a subset of signals provided by the plurality of antennas, a maximum ratio combiner for summing the selected subset of signals provided by the plurality of antennas, and a decision device for measuring the selected subset of signals against a predefined threshold. The device for selecting the subset of signals is coupled to the plurality of antennas. The maximum ratio combiner is coupled to the selected subset of signals and the decision device for measuring the selected subset of signals against a predefined threshold. The decision device is coupled to the selecting device such that one selected signal of the selected subset of signals is replaced by an unused signal provided by the plurality of antennas.

Abstract: The invention concerns a method of estimating the noise power of a given digital signal (cell1) assigned a code, this signal being received by a receiver (56) simultaneously with a plurality of other digital signals assigned different codes. The noise powers are estimated for each of the received digital signals (cell1, cell2, . . . cellM) assigned codes and there is assigned, to the given signal, the mean noise power (62) which is the ratio between, on the one hand, the sum of the estimated noise powers and, on the other hand, the total number M of received codes.

Abstract: A system and method for impulse radio power control wherein a first transceiver transmits an impulse radio signal to a second transceiver. A power control update is calculated according to a performance measurement of the signal received at the second transceiver. The transmitter power of either transceiver, depending on the particular embodiment, is adjusted according to the power control update. Various performance measurements are employed according to the current invention to calculate a power control update, including bit error rate, signal-to-noise ratio, and received signal strength, used alone or in combination. Interference is thereby reduced, which is particularly important where multiple impulse radios are operating in close proximity and their transmission interfere with one another. Reducing the transmitter power of each radio to a level that produces satisfactory reception increases the total number of radios that can operate in an area without saturation.

Abstract: Method of reducing transmission power across a loop in a discrete multitone communication system. A first signal to noise ratio (SNR) is estimated for a signal transmitted across the loop. A second SNR is estimated for a signal across the loop, the second SNR signal being estimated exclusive of a predetermined portion of the first SNR. A power cutback scaling factor is determined in accordance with the first SNR, the second SNR, and a predefined maximum SNR degradation amount. The transmission power is scaled in accordance with said scaling factor for reducing said transmission power. In such a manner, fine gains are computed such that the transmit power is reduced without significantly affecting the achieved data rate.

Abstract: A technique for de-assigning signals from the fingers of a rake receiver is disclosed. In general, embodiments of the present invention place more stringent standards on signals that have been newly assigned to a finger and may be spurious and place less stringent standards on mature signals that have proved themselves over time but may be experiencing only a temporary signal quality shortfall. Illustrative embodiments of the present invention accomplish this goal using one or more of four techniques. The first technique de-assigns a signal from a finger when a measure of signal quality of the signal crosses a threshold, while changing the threshold as a function of the duration that the signal has been assigned to the finger.