Abstract: The frequency doubler of the present invention operates to provide an in-phase signal and a quadrature signal, each having a frequency equal to twice the frequency of a reference signal. The in-phase and quadrature signals are based on signals that are 0 degrees, 45 degrees, 90 degrees, and 135 degrees out of phase with the reference signal. The in-phase signal is provided by multiplying the signals that are 0 degrees and 90 degrees out of phase with the reference signal, and the quadrature signal is provided by multiplying the signals that are 45 degrees and 135 degrees out of phase with the reference signal.

Abstract: A multi-hop wireless, for example cellular, communications system is provided comprising a source equipment which may be one of a base station or an end user terminal for transmitting signals towards a destination equipment which may be the other of a base station or an end user terminal via at least one relay equipment. The relay equipment receives a plurality of signals transmitted from one or more source equipments of the system and from this plurality of signals selects a signal to relay. In this way the decision about which relays are included in which communication paths in the system is distributed to the relay equipments of the system, thus reducing the signalling overhead as compared with link state protocols which are typically used for routing in such multi-hop systems.

Abstract: A method of estimating the operating characteristics of a communication unit in a radio network in which a plurality of such communication units can communicate with a plurality of terminals by means of wireless signals and in which the terminals and the communication units are capable of macro-diversity communication whereby a terminal may simultaneously communicate with a plurality of the communication units, the method comprising: estimating for the communication unit and neighboring communication units the propagation characteristics of signals to and/or from each such communication unit, in a manner specific to that respective communication unit; determining based on at least the estimated propagation characteristics and the relative locations of the communication unit and the neighboring communication units a representation of at least one of the macro-diversity gain for the communication unit and the fading margin for the communication unit.

Abstract: In a satellite or other relayed communication system having a plurality of subscriber terminals that communicate through an elevated wireless relay (typically a satellite operating in bent pipe mode), a technique for subscriber terminal power control is provided whereby the power level is controlled via leader-follower operation relying on sharing control factors determined at a single calibrated subscriber terminal transmitter (the leader terminal) to create traffic to be compared to the received traffic of the other subscriber terminals. The power level of the subscriber terminals is then adjusted based on the relationship of their received energy to the received energy of the leader terminal.

Abstract: A wireless repeater and controller is placed between a light socket and a light bulb, such as in a ceiling light fixture. The wireless repeater and controller has an extending threaded portion that screws into the light socket, and a recessed threaded portion that receives a light bulb. When the light switch that would normally control the light bulb is on, power is provided to the wireless repeater and controller. When the power to the wireless repeater and controller is toggled on then off using the light switch, the wireless repeater and controller disconnects line power from the light bulb so the light switch can still be used to control the light bulb.

Abstract: The present invention provides a search window delay tracking procedure for use in a multipath search processor of a CDMA radio receiver. A channel impulse response is estimated for a received signal containing plural paths, each path having a corresponding path delay. A search window defines a delay profile that contains the plural paths of the received signal. A mean or average delay is calculated for the estimated channel impulse response (CIR), and an error is determined between the mean CIR delay and a desired or target delay position of the Cir. search window. An adjustment is made to reduce that error to align the targeted position of the search window and the mean CIR delay. A Doppler frequency is estimated for each path. The adjustment is made taking into account a Doppler effect caused by relative movement between the transmitter and receiver.

Abstract: A method and apparatus are provided for adjusting a communication receiver based on the velocity of a wireless communication device in relation to a base station. The receiver is adjusted by estimating a frequency shift of a communication signal transmitted between the base station and the wireless communication device (WCD) based on the WCD velocity. Using this estimate, adjustments are made to the communication receiver to account for the frequency shift of the communication signal. Adjustments to the receiver can include adjusting frequency and time tracking loops to account for the change in frequency of a signal received by, and from, the WCD as it moves relative to the base station. The receiver may be located in the WCD, or in the network infrastructure, or in both.

Abstract: A method and apparatus for assigning the data rate and/or power level to the mobile terminals without determining the highest theoretical system throughput, and without determining the highest weighted system throughput. An order is imposed on the terminals and the data rate and/or power covariance matrices are assigned such that the data rates of the terminals having a lower index in the order will not be decreased due to the presence of the terminals having a higher index in the order, and this is accomplished without changing the power covariance matrixes of the antennas involved in the communication with the lower index terminals. Thus, the assignment is made to the terminals based on the terminals requirements without regard to the interference introduced by the terminals with a higher index in the order since this interference will be compensated for by the compensation technique when the compensation technique process the terminals in accordance with the order.

Abstract: This invention is directed toward improving the subjective voice quality of a mobile to mobile phone call having tandem vocoder processing by modifying the spectrum of the voice signal before it is processed by the second vocoder to compensate for digital distortion which is generated by the second vocoder. An adaptive filter can be used to modify the spectrum of the voice signal. With this invention, the voice quality of a call from a first mobile phone to a second mobile phone has a quality that is substantially similar to the voice quality of a call from a mobile phone to a desk phone.

Abstract: Duplicate participants (e.g., cloned subscriber units) (274) are detected in a communication network, such as a hybrid fiber/coax (HFC) cable television network or the like, by monitoring the physical layer of the network to detect transmission differences between such units. The subscriber units (14, 16, 18, 274, 276) may be cable modems that transmit upstream signals with associated identifiers to a headend (10, 200), e.g., to access the Internet or for telephony. Measured characteristics of the upstream signals can include: (1) propagation time (235), (2) frequency (240), (3) power (245), and (4) spectral characteristics (250). For propagation time, the reception time of the upstream message can be compared to a headend clock (215) and also to other messages with the same modem ID. For spectral characteristics, adjustment coefficients can be provided to the units to normalize the spectrum of the upstream signal to a baseline spectrum.

Abstract: A symbol combining device for multi-path diversity includes a plurality of demodulation circuits for demodulating received signals, a common memory for storing outputs of the demodulation circuits, a symbol combiner for receiving the outputs of the common memory corresponding to the demodulation circuits and for combining the outputs, and a memory controller for controlling the common memory to timely separate the write and read operations. To timely separate the write and read operations, the memory controller controls the common memory in order that the demodulation circuits sequentially access the common memory and the resultant outputs of the demodulation circuits are written in the common memory, and the symbol combiner reads the outputs of the demodulation circuits written in the common memory sequentially.

Abstract: An apparatus for testing a cellular phone comprising an RF signal generator (122) for transmitting an RF signal (RF10) to said cellular phone, said RF signal generator receiving an input digital signal (DSIG10) which determines the characteristics of the RF signal, means (112, 116) for providing said input digital signal comprising means for receiving a digital signal (DSIG4, DSIG5), and at least one set of digital means, each set (A, B, C) of digital means comprising: a first digital means (200, 201, 202) to provide a first digital signal element relating to a first characteristic of said RF signal, and a second digital means (MA, MB, MC) to provide a second digital signal element relating to a second characteristic of said RF signal, and a means (203) to combine said digital signal elements to provide said input signal to said RF signal generator, said first, second and third characteristics comprise phase, amplitude and delay respectively.

Abstract: A method and apparatus to compensate for interference between signals within a wireless communication system using dirty paper coding to compensate for interference on the downlink and multi-user detection to compensate for interference on uplink.

Abstract: A method (500) and a mobile station (160) for reporting multi-path signals based on a report window are described herein. The mobile station (160) may determine a distribution of a plurality of multi-path signals observed by a receiving unit (220) within the mobile station (160). The mobile station (160) may determine a report window based on the distribution. Based on the report window, the mobile station (160) may report at least one of the plurality of multi-path signals.

Abstract: A method and/or an apparatus for mitigating intersymbol interference. In systems which employ transmission diversity when transmitting symbols which have a guard interval, the multiple versions of the transmitted symbols have the samples of the transmitted symbols shifted relative to each version transmitted. The shifted samples of the transmitted symbol are shifted from the end of the transmitted symbol into the beginning of the transmitted symbol. A last number of samples of the transmitted symbol are copied and placed in the guard interval which precedes the symbol. The guard interval and the symbol are transmitted to a receiver.

Abstract: A method and apparatus for detecting oscillation in a repeater system is disclosed. More particularly, in one embodiment, a wireless communication device is embedded in a repeater system and is configured to detect if the repeater system is in oscillation. A processor coupled to the WCD is configured to reduce the gain of the repeater system if the repeater system is in oscillation.

Abstract: The present invention relates to wireless communication networks particularly for indoor deployment, in which there typically directly exists a rapidly changing multipath propagation environment with limited opportunities for line of sight wireless communication. The present invention provides A wireless communications network for communicating with a mobile terminal; comprising: a number of repeater points each comprising means for communicating with the mobile terminal; an access point comprising means for communicating with the repeater points; the repeater points further comprising means for relaying signals between the terminal and the access point; means for determining a quality measure of signals sent by the terminal and received by the access point via the repeater points; means for selecting one or more repeater points to relay transmission signals from the access point to the terminal, said selection based on said quality measures of the terminal signals received by the access point.

Abstract: A method and system for compensating for atmospheric fading is used in a communication system wherein communication signals are exchanged between first and second earth stations via a satellite link, without increasing power of the satellite link. The method includes determining, at one or both of the earth stations, the signal power of a received signal and a signal-to-noise ratio of the received signal; calculating the difference in noise power spectral density in the received signal from that under clear sky conditions; calculating the downlink attenuation; determining the uplink attenuation, and commanding the transmitting earth station to increase its transmit power by an amount to compensate for the uplink attenuation. A corresponding system carries out the method.

Abstract: A repeater system combines co-located antennas, limited and controlled downlink signal amplification, stability management and an amplification indicator to create a user-installed solution to co-channel interference within cellular systems, in strong signal environments such as elevated locations or high-rise building. The invention may be particularly relevant to cellular systems, such as CDMA, that allow limited imbalance between uplink and downlink path losses, thus enabling the design of an inexpensive downlink repeater which creates moderate signal amplification for selected line-of-sight signals, defeating co-channel interference over a small area. Signal amplification is maintained at a level below the capacity of the system to support imbalance, guaranteeing reliable cellular calls.

Abstract: [Object] The invention provides a UWB repeater preferably applied to a relay of stream data, which does not require frequency conversion and has less delay in relay.

Abstract: The invention relates to a method of adjusting the radio frequency of a repeater (302) in a cellular radio network. The repeater (302) amplifies radio signals (170) of a bi-directional radio connection between a base station (100) and a subscriber terminal (150) at least at one particular radio frequency. In accordance with the invention, the repeater (302) monitors the radio signals (170) transmitted by at least one base station (100). The repeater (302) automatically tunes to amplify the signals (170) of the particular radio frequency on the basis of information included in the radio signals (170) it has monitored. The monitored radio signals (170) include a control channel, for example a broadcast control channel BCCH, comprising information on the operating frequencies of the base station (100). Monitoring means (404) are preferably similar to a subscriber terminal (150).

Abstract: A system and method reduce power consumption in a multi-hop wireless communications network. A signal is received from a source node in an intermediate node. The signal includes a request to relay a message to a destination node. The request includes information on power requirements to relay the message either in a relay mode or a regeneration mode. If the available power at the intermediate node exceeds the power requirements, then the request is accepted. Either the relay mode or the regeneration mode is selected, based on criteria for retransmitting the message, and the message is then relayed to the destination node using the selected mode.

Abstract: A method and apparatus for controlling uplink transmission power in a satellite communication system is disclosed. The satellite communication system includes a satellite and one or more earth stations, one of which serving as a control station. The satellite can receive uplink signals from any one of the earth stations and retransmits the uplink signals as downlink signals, along with a beacon signal. The control station measures the power of the downlink signals and the beacon signal received from the satellite, and also measures the noise power near the beacon signal. From these measurements, the control station determines an appropriate gain value of the power for uplink transmissions for each of the earth stations.

Abstract: A method for providing power control to a uplink signal, comprising an uplink station transmitting an uplink signal to a satellite. The satellite also transmits a loopback signal representing the received uplink signal back to the uplink station. The satellite also transmits a beacon signal to the uplink station. The uplink station adjusts the power of the uplink signal based on measurements of the beacon signal and the uplink signal.

Abstract: A method and apparatus for reducing deep fading of signals in satellite-based communications systems employing terrestrial repeater stations by shifting the phase of the signals transmitted from each terrestrial repeater station by a different amount so that the signals are transmitted from each terrestrial repeater station and received at a receiver at different phases, thereby effectuating time diversity in such signals to reduce deep fading of the signals. The method and apparatus can be used in CDMA and OFDM systems.

Abstract: In data transmission between a host device and a target device connected by a serial bus, when commands and data use the same register area, and only the transmission result of the data is to be returned, any command other than a data transmission command cannot be transmitted for a certain period because the receiving-side register becomes full. In this invention, when a response to a data transmission command from the host device is to be returned from the target device, the host device is notified of the situation of the data receiving buffer. The host device transmits a DUMMY command to the target device in accordance with the free buffer situation and transmits another command to the target device in accordance with the response from the target device. The target device sends a data retransmission request to the host device in accordance with the free buffer situation.

Abstract: A method (500) and a mobile station (160) for reporting multi-path signals based on a report window are described herein. The mobile station (160) may determine a distribution of a plurality of multi-path signals observed by a receiving unit (220) within the mobile station (160). The mobile station (160) may determine a report window based on the distribution. Based on the report window, the mobile station (160) may report at least one of the plurality of multi-path signals.

Abstract: A repeater for use in a two way communication system for retransmitting information between a first device and a second device to help ensure reliable two way communication between the devices, comprising: a transmitter/receiver, the transmitter/receiver receiving signals from the first and second devices and transmitting the received signals for reception by the respective first and second devices; and further wherein a direct communication path for the information between the first and second devices is provided, the direct communication path being intermittently unreliable, the repeater providing an additional path for the information between the first and second devices; the repeater being spaced from said first and second devices by a specified distance, said specified distance being significantly less than a theoretical maximum communication distance thereby to ensure communication reliability.

Abstract: In order to retransmit a communication channel at a specific frequency, a receiver may receive a signal including the communication channel's specific frequency. An analog to digital converter may generate a digital signal correlated to the received signal and the digital signal may be passed through a digital filter configured to filter the digital signal and pass frequency components at or around the frequency of the communication channel's specific frequency. A digital to analog converter may generate an analog signal correlated to the filtered digital signal and a transmitter may transmit the analog signal.

Abstract: A point-to-point, wireless, millimeter wave trunk line communications link at high data rates in excess of 1 Gbps and at ranges of several miles during normal weather conditions. This link is combined with an Ethernet network to provide high speed digital data communication among a large number of users. In a preferred embodiment a trunk line communication link operates within the 92 to 95 GHz portion of the millimeter spectrum. A first transceiver transmits at a first bandwidth and receives at a second bandwidth both within the above spectral range. A second transceiver transmits at the second bandwidth and receives at the first bandwidth. The transceivers are equipped with antennas providing beam divergence small enough to ensure efficient spatial and directional partitioning of the data channels so that an almost unlimited number of transceivers will be able to simultaneously use the same spectrum.

Abstract: A system for reducing multipath interference in a wireless data transmission generally includes a processor and memory device for capturing one or more data packets of the wireless data transmission. The transmitting device associates a time value and/or a spatial value to each of the data packets. Upon capture, the processor determines whether the captured data packet is reflective or non-reflective by comparing the time value or spatial value, as applicable, of the captured data packet to the time value or spatial value of each stored non-reflective packet. The system identifies the captured data packet as non-reflective, if the time value (or spatial value) of the captured packet is different from the time value (or spatial value) of each stored non-reflective packet.

Abstract: A method for providing wireless transmission diversity wherein an error correcting codeword is divided into first and second segments at first and second transmitting units. The first segments are transmitted from each of the first and second transmitting units and received at the first and second transmitting units, respectively. The received first segments are decoded and, responsive to the decoding, transmission of a second segment is made from each of the first and second transmitting units.

Abstract: In data communication utilizing a radio transmission channel, even in a case where the radio channel is disconnected and a data communication blackout occurs, the center side continues data communication processing, by obtaining information on a period where the data communication is interrupted in advance. The system comprises an application server provided in the center, a radio data communication terminal that performs data communication while moving, a mobile gateway provided in the center as a relay device between the application server and the radio data communication terminal, and a period notification device that transmits period information T at predetermined periods. The radio communication channel is disconnected by the period information transmitted from the period notification device, and the mobile gateway performs communication processing during the radio communication disconnection.

Abstract: A point-to-point, wireless, millimeter wave communications link providing data transmission rates of over 1 billion bits per second (more than 1 Gbps) at ranges of several miles during normal weather conditions. In a preferred embodiment a communication link operates within the 92 to 95 GHz portion of the millimeter spectrum. A first transceiver transmits at a first bandwidth and receives at a second bandwidth both within the above spectral range. A second transceiver transmits at the second bandwidth and receives at the first bandwidth. The transceivers are equipped with antennas providing divergence of less than 10−4 steradians so that an almost unlimited number of transceivers can use the same spectrum. In a preferred embodiment the first and second spectral ranges are 92.3-93.2 GHz and 94.1-95.0 GHz. During very bad weather conditions this data link will not provide a 10−10 bit-error rate and 99.999% availability.

Abstract: A pilot signal detection method and a receiver, in which a search window having a predetermined time width is generated at every substantially constant time interval, and pilot signals existing in search window thus generated are detected. The position of the search window of each period is set in accordance with the delay amount between the timing (T_ref) of the first pilot signal and the timing (T_last) of the last pilot signal detected in the immediately preceding search window.

Abstract: A method and apparatus for effectively monitoring quality of a traffic channel in a communication, and in response, modifying transmission coding or data transmission rates, or both, improves communication quality and increases data transfers rates in digital wireless communication systems. A channel quality estimator determines and evaluates the bit error rate (BER) of a signal on a control channel and estimates the quality of the traffic channel based on the quality of the control channel signal. Accordingly, the processing and control circuitry of either a mobile station or base station adjusts the error correction applied to traffic channel transmissions. The traffic channel data transmission rate may also be modified based on the control channel signal quality.

Abstract: The present system comprises a transmitting apparatus for digital broadcast which includes an original signal generating section, delaying section, information amount reducing section, and transmitting section. A receiving and reproducing apparatus for digital broadcast includes a signal reception front stage unit for receiving a high quality signal and a low quality signal, mode determining section and reproducing section composed of a delaying section and selecting section for selectively reproducing the high quality signal and the low quality signal. By employing time diversity, the transmitting apparatus sends the low quality signal having a smaller bandwidth and the high quality signal so that the low quality signal has a preceding time lag relative to the high quality signal, and the receiving apparatus reproduces broadcasting programs. Utilizing the frequency band for broadcast effectively, many broadcasting programs can be increased, and the investment for providing a gap filler can be minimized.

Abstract: A photonic device including an array of lasers providing light to an array of electro-absorption modulators, both on a common substrate. In some embodiments the lasers are in a closely spaced array and lase at different wavelengths, providing with associated electro-absorption modulators a compact wavelength selectable laser.

Abstract: A symbol combining device for multi-path diversity includes a plurality of demodulation circuits for demodulating received signals, a common memory for storing outputs of the demodulation circuits, a symbol combiner for receiving the outputs of the common memory corresponding to the demodulation circuits and for combining the outputs, and a memory controller for controlling the common memory to timely separate the write and read operations. To timely separate the write and read operations, the memory controller controls the common memory in order that the demodulation circuits sequentially access the common memory and the resultant outputs of the demodulation circuits are written in the common memory, and the symbol combiner reads the outputs of the demodulation circuits written in the common memory sequentially.

Abstract: Methods are provided for determining and enhancing the service efficiency of mobile communications. To assess communication efficiency in each communication region of interest, a signal-fading record is generated for that region and this record is then analyzed to find availability and energy cost for each of a plurality of power-control parameter sets. The results facilitate the selection of power-control parameter sets that enhance system efficiency in each communication region.

Abstract: The present invention provides an open-loop method for determining uplink transmission power in a satellite communication system 200 that compensates for antenna pointing error attenuation and for rain attenuation. Satellite downlink signal 208 attenuation is measured. Antenna pointing information is then used in conjunction with antenna gain pattern information 400 to determine antenna pointing error attenuation. The measured downlink attenuation and antenna pointing error attenuation are then used to determine the amount of rain attenuation on the downlink 208. The downlink attenuation information is then used to determine the amount of uplink 216 attenuation to be expected. Uplink transmission power levels are then adjusted accordingly to overcome the expected uplink 216 attenuation.

Abstract: The present invention pertains to the field of methods and apparatuses relating to radio communication; and in particular to the part of this field that concerns cellular radio communication. The present invention addresses mainly the problem of improving reliability and communication quality in a cellular radio communication system (1). According to the invention, it is determined whether one of an uplink (25) or a downlink (25) of a radio channel (23) is subject to a Rayleigh fading dip. If it is determined that one of the uplink (25) or the downlink (27) is subject to a Rayleigh fading dip, it is then determined whether it is necessary to execute a countermeasure in order to avoid the negative influences of Rayleigh fading on the channel (23). The invention is not limited to improving conditions on one channel but may be employed to any number of channels used for communications in the cellular radio communication system (1).

Abstract: An apparatus for transmitting information comprises a bitstream source for providing a bitstream representing the information, a redundancy adding encoder for generating an encoded bitstream, which is arranged to output, for a first number of input bits, a second number of output bits, the second number of output bits having at least twice as many output bits as the first number of input bits, wherein the second number of output bits includes two portions of output bits, each portion of output bits individually allowing the retrieval of information represented by the first number of input bits, and the first portion of output bits being coded based on the bitstream in a different way with respect to the second portion of output bits.

Abstract: Methods are provided for determining and enhancing the service efficiency of mobile communications. To assess communication efficiency in each communication region of interest, a signal-fading record is generated for that region and this record is then analyzed to find availability and energy cost for each of a plurality of power-control parameter sets. The results facilitate the selection of power-control parameter sets that enhance system efficiency in each communication region.

Abstract: In a time division duplex (TDD) system, compensation measurements are made for the transmission circuitry during the receive portion of the TDD cycle and compensation measurements are made for the receive circuitry during the transmit portion of the TDD cycle. A base station has multiple antennas for spatial, as well as spectral, spreading and despreading of discrete multitone spread spectrum (DMT-SS) communications. Each antenna has its own transmission path components and receive path components. The transmit amplifier, for example, in the transmit path and the receive amplifier, for example, in the receive path tend to drift in their characteristics over time. The invention manages the sequential testing of each respective transmission path and receive path for each antenna. The invention measures the drift of the transmit path components and the receive path components and prepares compensating weights to be applied to signals processed in each path.

Abstract: A method and apparatus for evaluating signal strength of a channel received at a mobile station within a spread spectrum communication systems is disclosed. If the receiver at the mobile station receives a spread spectrum signal, a first sampling means converts the received signal into a first sample stream as a first sampling. A second sampling means converts the first sample stream into a second sample stream at a second sample rate, different from the first sample rate. The signal strength of a pilot channel is measured based upon the first and second sample streams.

Abstract: A method of interleaving data for transmission is provided wherein first and second interleaving patterns for arranging data symbols in a source data stream into first and second transmitted data streams are selected. Each of said data symbols has at least one bit. The first and second transmitted data streams are transmitted substantially simultaneously on separate transmission channels to at least one receiver. The first and second patterns are used to transmit the data symbols in the source data stream in a different order on the respective transmission channels to maximize recovery of the source data stream when the transmission channels are blocked. The selected interleaving patterns can involve reordering the data symbols throughout the first and second transmitted data streams using different reordering criteria. The reordering criteria can vary on a frame-by-frame basis if the source data stream is time division multiplexed. Complementary data can be sent on respective transmission channels.

Abstract: A communication satellite system dynamically allocates additional downlink resources on the satellite to selected downlink signals to compensate for signal degradation. A typical cause of such degradation is rain where the downlink station is located. Another cause of such degradation is increased communication traffic or bandwidth demand within a particular region.

Abstract: A method and apparatus predicts a ground-to-satellite terminal's (16) percentage of successful communication linkage time to at least one satellite of a communication system in response to a terminal blockage profile (410), as created from the location of an antenna of the terminal, and a satellite blockage profile (412). The prediction may also be based upon a weather model data base (358) corresponding to the area where the terminal is located.

Abstract: A communication system and methodology are implemented to anticipate periodic or predictable disruptions of communications in a satellite communication network. The communication system and methodology then compensate for this disruption in an appropriate manner. Such prediction and compensation actions are performed for a selected group of subscribers ("premium" subscribers) who wish to originate or receive telephone calls during the period of time that the outage or disruption occurs. To compensate for such predictable outages, the communication network takes advantage of the multiple gateways typically implemented within mobile satellite communicate networks. Rather than using the multiple gateways for redundancy, the communication network and methodology recognize that the multiple gateways may also be used for the alternate routing of telephone calls, particularly during a period of time in which the outage occurs. Through this methodology, a "virtual routing" operation may be executed.