Abstract: A receive control portion activates each of VCOs, and then sets a reference dividing ratio Ntyp in the programmable divider. With each of the VCOs active, the receive control portion determines whether the PLL circuit locks or not based on a signal inputted during this time. Based on the determination result, the receive control portion then creates pattern data in a first table. A second table is previously stored in memory. Written into the second table is an optimal VCO for each pattern. The receive control portion determines the optimal VCO corresponding to the created pattern data referring to the second table. This allows the receiver to optimally select a VCO at high speed.

Abstract: A multi-carrier transmission system and a method thereofor employing a bit distribution method capable of solving the problem set forth above by regarding a plurality of SNR values evaluated at different timings as one SNR value evaluated at different frequency at the same timing and is capable of solving the problem set forth above by realizing a given transmission speed depending upon a plurality of SNR values evaluated at different timings and thus maximizing performance margin.

Abstract: A method of sending information includes sending, on a transmission channel, sequences of symbols. The sequences are of a fixed length that is not a multiple of 4 and are taken from a collection of sequences, at least three of which are orthogonal in pairs and such that any pair of sequences that is not orthogonal to each other comprises opposite sequences. The symbols are taken from an alphabet of non-nil integers.

Abstract: An Amplitude Shift Keying (ASK) modulating circuit includes an oscillation circuit generating a pulse oscillation having a given frequency. A frequency divider is provided having a binary counter unit and having at least an input terminal, an output terminal and a reset terminal. The frequency divider is active and inactive when the reset terminal thereof is applied with low and high levels of a transmission signal wave, respectively, and divides the pulse oscillation while the frequency divider is active. The transmission signal wave is modulated together with a carrier frequency which is identical to the divided frequency.

Abstract: A system for transmitting information from a source to a destination using multilevel signaling. Multiple conductors are coupled between the transmission source and the transmission destination. Multiple drivers are coupled to the conductors at the transmission source. Each driver is coupled to a pair of conductors. Multiple comparators are coupled to the conductors at the transmission destination. Each comparator is coupled to a pair of conductors. The information is encoded into a sequence of symbols in which each symbol represents a unique permutation of signal levels on the conductors. Each signal level is used at least once for each symbol. All signal levels associated with a particular symbol are transmitted over the conductors simultaneously.

Abstract: The invention enables to estimate the frequency offset introduced by a transmission medium based on the transmission of a known sinusoidal-frequency signal. Two samples out of phase by Π/2+p.2Π where p is an integer are multiplied to obtain a trigonometric function of said frequency offset. The estimate thus obtained is advantageously applied for correcting test signals received during a learning period preceding a transmission period between a transmitter and receiver. The estimate is also applicable for initializing adaptive algorithms for recovering the timing or echo cancellation at the level of the receiver. Any transmission system that utilizes one or various carriers and enables to transmit a sinusoidal signal at a given instant, notably Recommendation V34 of the CCITT.

Abstract: A communications system includes a first and second modem coupled together via a communications link. The first modem has at least two user devices coupled thereto, and modulates data generated by the user devices on a plurality of tone carriers for transmission to the second modem. The first modem determines the number of user devices coupled to it. Based upon the number of user devices determined, the first modem divides the plurality of tone carriers into a number of subsets corresponding to the number of user devices based upon a predetermined criterion. The first modem then allocates a subset of tone carriers to a respective user device. In one embodiment, the usage rate of each user device is determined, and the tone carriers are reallocated to different subsets as a function of the usage rate of each respective user device.

Abstract: A method of transmitting a quite, or zero, signal in a PCM communication system. The zero signal is specified universally in ordered set terms for either &mgr;-Law or A-Law PCM systems, which has minimal energy in the A-Law system, and contains no energy within the &mgr;-Law system. The signal is preferably specified as a repetition of six intervals (or multiple thereof) because the DTN can modify PCM codes on a six interval period by the robbed-bit signaling mechanism. The zero signal may be used to detect network elements that produce single-signed zero outputs from zero inputs of either sign. In addition, by examination of the zero signal the receiver may determine whether the channel includes an analog link or connection.

Abstract: An integrated sigma-delta radio frequency (RF) receiver subsystem (200) and method utilizes a multi-mode sigma-delta analog-to-digital converter (215) for providing a single and multi-bit output. A programmable decimation network (221) for reducing the frequency of the in-phase and quadrature bit stream and a programmable formatting network (223) are also used for organizing the in-phase and quadrature components from the decimation network (221) for subsequent signal processing. The invention offers a highly integrated digital/analog RF receiver back-end which incorporates integrated filtering and a smart gain control that is compatible for use with other receiver systems and offering superior performance characteristics. Dynamic programmable interference mitigation is provided which facilitates power reduction and use in multi-tier products.

Abstract: A system and method for transmitting data between a first and second ADSL DMT modem. The system includes a plurality of user devices coupled to the first modem for generating user data. A buffer, coupled between the user devices and the first modem, accumulates a predetermined amount of user data. When the predetermined amount of user data is accumulated in the buffer, the first modem modulates the predetermined amount of accumulated data to generate a DMT symbol, and transmits the symbol to the second modem. The second modem, upon receiving the symbol, demodulates the symbol and recovers the user data respectively corresponding to each of the user devices.

Abstract: The invention relates to a phase detector. The phase detector includes data sampling cells to sample a stream of serial data and generate primary data samples and also includes edge data sampling cells to sample the stream of serial data and generate edge data samples. The phase detector further includes phase detecting cells to generate phase control signals. Each phase detecting cell includes a first circuit to receive data and sampled edge data and to generate a first signal and a second signal. The first signal from a phase detecting cell is a delayed sampled edge data. The second signal from that phase detecting cell will be a delayed sampled edge data before data is sampled by the data sampling cell. Once data is sampled by the data sampling cell, the second signal from that phase detecting cell will be a secondary data sample. Each phase detecting cell also includes a comparator circuit to receive the first signal and second signal and to generate a phase control signal therefrom.

Abstract: An approved demodulator is disclosed for demodulating optical ASK data signals whose data bits are each characterized by either an absence of pulses or a burst of pulses at a predetermined frequency. The demodulator includes an amplifier tuned to this predetermined frequency, and it further includes an edge detector that produces an envelope of the amplified signal. A comparator then compares the envelope signal with a prescribed threshold, to produce a pulse signal for each received burst of pulses. The duration of this pulse signal is then stretched so as to correspond to the pulse burst's expected nominal duration. The demodulator is specially configured such that it can properly demodulate ASK data signals having power levels that vary over a range of several orders of magnitude.

Abstract: The invention relates to a frequency hopping method and a radio system. Frequency hopping is implemented downlink to the frequency of the broadcast control channel. The radio system comprises a network part (100), a subscriber terminal (102) and a radio connection (104) as the transmission path. The novelty is that the broadcast control channel does not usually perform frequency hopping. The simplest implementation of the system is a software modification in the network part (100) and the subscriber terminal (102). The invention can be applied to all radio systems using frequency hopping, particularly to the GSM/DCS 1800 systems and the UMTS system.

Abstract: A technique for spreading information signals in a spread spectrum communication system to provide increased signal acquisition speed. A first PN spreading code or code set is used to spread information signals along with a second PN spreading code sequence or function. The second PN code is synchronized with the first PN spreading code, but has a larger code period so that each code chip of the second PN code extends over the entire period of the first PN code. The longer period spreading code forms an outer code which helps provide unambiguous beam identification and easily acquired frame timing in the presence of dynamically changing signal path delay, improving signal acquisition.

Abstract: This invention relates to a digital communication bus between electronic modules (S1, Sn), composed of at least one pair of data transmission lines (2A, 2B) and terminating by line terminators (TA, TB), and characterized by the fact that it comprises, for example in the two line terminators (TA, TB), components (R6, R7, R3, R4) imposing transmission with polarization and inverting the polarization whenever one or both line terminators are missing, or are not connected to the bus, or the bus is open.

Abstract: A method for carrying out code synchronization when a signal has been spread-coded by a pseudo-random spreading code. The method comprises forming angular cells (400, 402, 404, 406, 408, 410), determining interference power in each angular cell (400, 402, 404, 406, 408, 410), arranging the angular cells (400, 402, 404, 406, 408, 410) according to the interference power, carrying out code acquisition by examining the arranged angular cells (400, 402, 404, 406, 408, 410) by using different delays of the spreading code, starting from the angular cell with the lowest interference power. The angular cells (400, 402, 404, 406, 408, 410) can e.g. be arranged as a vector in ascending order according to the interference power. The method comprises determining the number of angular cells to be formed e.g. by means of an estimated interference power.

Abstract: An orthogonal frequency division multiplexed wideband communication system provides improved time and frequency synchronization by inserting an unevenly spaced pilot sequence within the constellation data. A receive correlates the received data using the unevenly spaced pilot sequence. The pilot sequence is generated with a maximum length pseudo random noise code and inserted into frequency bins having prime numbers.

Abstract: A method and device for the testing of a radiocommunications network by implementing downline from a first antenna and a second antenna, respectively a first reception line and a second reception line. The first reception line is assigned to the reception of first signals, in a first incoming direction. A second reception line is assigned to the reception of second signals, in a second incoming direction. Each reception line tries to decode the signals that it receives and, if the decoding can be done, it reads an identifier proper to the transmitter, so as to determine firstly which of said first and second signals are interference signals, and, secondly, the incoming direction of interference signals and/or the identifier of interference units. The disclosure also relates to a corresponding base station.

Abstract: When a change of an output signal is detected by an output-signal-state-change detector, a continuous-change performing part controls an output impedance changing part, which is provided between an output buffer and a signal line, so as to continuously change an output impedance from low impedance to high impedance, at the changing timing of the output signal.

Abstract: A method of determining digital channel attenuation; comprising the steps of: receiving a known training sequence of PCM codes, which PCM codes are subjected to the attenuation within the digital channel; quantizing the received known training sequence of PCM codes according to a predetermined thresholding procedure; identifying identical PCM codes created as a result of the thresholding procedure; and, determining the attenuation of the digital channel based upon the identification of identical PCM codes. A method is also disclosed for determining a digital channel PCM code transformation comprising receiving a known training sequence of PCM codes, which PCM codes are subjected to the PCM code transformation within the digital channel, quantizing the received known training sequence of PCM codes according to a predetermined thresholding procedure, and determining the transformation of transmitted codes to those received.