Abstract: Increased data rate transmission in the reverse traffic channel is obtained by modifying a core reverse CDMA traffic channel signal generator and modulator by creating a plurality of parallel pathways, each of which includes a Walsh modulator and a modulo-2 adder which direct-sequence spreads the modulated data using one of a plurality of modified long codes. The DS-spread data signals from each of the parallel pathways are summed and split to the I and Q channels for PN code spreading. The long code variations are obtained by varying one or more bits of the IS-95 standard public long code mask or private long code mask, specifically, one or more bits of the most significant bit (MSB) string of the public long code mask (bits M41 through M32). Generally, each variable bit provides two possible code channels—one Fundamental Code Channel and 2b−1 Supplemental Code Channels, where b is the number of bits that can be varied within the long code mask.

Abstract: A microprocessor reads the information such as directions of arrival about a desired wave and an undesired wave for every terminal station and for every hopping frequency, and their receiving powers, and the like, from a desired wave/undesired wave information inputting unit. On the basis of the information items, the microprocessor calculates the weight values of a transmitting section and a receiving section for every terminal station and every hopping frequency, and stores them in a weight value table. At the time of performing radio communication, the microprocessor reads the weight values of the receiving section and the transmitting section corresponding to every terminal station and every hopping frequency from the weight value table every time the frequency is hopped, and sets them in attenuators, and phase shifters. As a result, the optimum directivity pattern is formed for every hopping frequency, and high-quality communication can be thereby achieved.

Abstract: A cellular radio telecommunication system is described that allows the beacon frequencies in the system that distributes the common control channel to carry more traffic channels than the number of remaining TDM slots, by reusing the same slot in different parts of the network to carry different traffic to different mobiles. This is achieved by monitoring the location in the network of each mobile which is assigned to a traffic channel on the beacon frequency, using a controlling agent, and ensuring that any basestation assigned to the beacon frequency which is sufficiently close to this mobile transmits exactly the same data in the slot carrying this traffic channel, but otherwise allows the slot to be reallocated.

Abstract: A method and an apparatus for detecting a frequency correction burst embedded in a signal which includes ordered samples. The method comprises the following: (a) correlating K sequences of the ordered samples with a predetermined waveform to produce K correlation outputs, each of the K correlation outputs corresponding to one of the K sequences, having a magnitude and being associated with an order index, K being an integer, the predetermined waveform corresponding to the frequency correction burst; (b) storing the K correlation outputs in a buffer according to the order indices; and (c) estimating a parameter based on the K correlation outputs, the parameter indicating detection of the frequency correction burst. The estimated parameter includes a frequency error and an ending time of a frequency correction burst. A quality metric associated with each frequency error is also computed.

Abstract: A wireless network is provided that uses pseudo-static time slots. These time slots remain fixed in time unless and until a network controller specifically changes them and the network controller subsequently receives confirmation of the change. Times and durations of the pseudo-static time slots are only changed in small steps as each relevant device in the network acknowledges the step. To aid in allowing full coverage even during a change of active devices, when a transmitter and receiver are moved to a new time slot, the receiver is set to listen to both the old and the new time slots until the transmitter confirms that it has made the switch.

Abstract: A method of data transmission according to one embodiment of the invention includes encoding a set of data values to produce a corresponding series of ordered n-tuples. The method also includes transmitting, according to the series of ordered n-tuples, a plurality of bursts over a plurality n of frequency bands. Specifically, for each of the plurality of bursts, a frequency band occupied by the burst is indicated by the order within its n-tuple of an element corresponding to the burst. A bandwidth of at least one of the plurality of bursts is at least two percent of the center frequency of the burst. Information is encoded into an additional modulation, e.g., amplitude, width or polarization modulation, of at least one of the plurality of bursts.

Abstract: A head end terminal for a communication system using multicarrier modulation is described. The head end terminal includes a multicarrier modem adapted to receive upstream signals and to demodulate the upstream signals modulated on a plurality of orthogonal carriers in a first frequency bandwidth, the multicarrier modem including a polyphase filter adapted to selectively filter the received upstream signal to provide protection against narrowband ingress for the modulated orthogonal carriers and allow for scalable bandwidth usage in the upstream transmission, and a controller operatively connected to the multicarrier modem for controlling receipt of signals.

Abstract: A wireless communication device includes a reconfigurable antenna and one or more wireless transceivers coupled to the antenna. The reconfigurable antenna can be dynamically configured to transmit and receive wireless signals at a plurality of frequencies and bandwidths. A processor core is coupled to the reconfigurable antenna and the wireless transceivers. The processor core dynamically controls the configurations of the reconfigurable antenna and processes the wireless signals transmitted and received at the plurality of frequencies.

Abstract: Systems and methods for sharing a single decoder among data streams originating with multiple sources. Error correction coding techniques are modified to facilitate decoding of data from multiple sources multiplexed in the time domain at the decoder input. A single decoder accommodates multiple sources that have been encoded using disparate code rates. One application is an OFDM point to multipoint system.

Abstract: The invention provides a method and system for a wireless transport layer, such as for use in a wireless communication system. In a preferred embodiment, the wireless transport layer includes the capability for instructing customer premises equipment to adjust the physical characteristics on its communication link with the base station controller, and for instructing customer premises equipment to conduct further communications using those new physical characteristics. The wireless transport layer includes a number of provisions for adjusting communication between the base station controller and customer premises equipment in view of the prospect of adjusting physical characteristics for communication between the two end points. The use of a point-to-multipoint wireless channel provides services over a link whose parameters are continuously adapting to current conditions on a per-user basis.

Abstract: A method of data transmission according to one embodiment of the invention includes encoding a set of data values to produce a corresponding series of ordered n-tuples. The method also includes transmitting, according to the series of ordered n-tuples, a plurality of bursts over a plurality n of frequency bands. Specifically, for each of the plurality of bursts, a frequency band occupied by the burst is indicated by the order within its n-tuple of an element corresponding to the burst. A bandwidth of at least one of the plurality of bursts is at least two percent of the center frequency of the burst. Information is encoded into a polarity of at least one of the plurality of bursts.

Abstract: A system to provide fractional bandwidth data transmission includes a network processor, physical layer device, or link layer device {“data device”) and a plurality of link layer devices that are coupled to a plurality of input-output ports. The link layer devices are coupled in a serial daisy chain fashion and pass data via a plurality of data channels. The first linked layer device is coupled to the data device and receives data therefrom and the last linked layer device is coupled to the data device and transmits data thereto forming a ring network that includes all of the link layer devices and the data device. Data received from the data device is contained in data packets that contain a destination identifier and the data. Each link layer device receives input data packets and separates the data packets based on the destination identifier contained therein.

Abstract: Method of communication between a mobile station and a base station in a mobile communication system of IMT-2000 communication network basis, which is suitable for effective transmission of various multimedia information within a given channel capacity, the method including the steps of (1) when a mobile station receives a data transmission request, providing one portion of a period of a data frame with regular number and arrangement of down link slots and up link slots and the other portion of the data frame with irregular number and arrangement of down link slots or/and up link slots depending on characteristics and amount of subscribe data to be transmitted, (2) determining a transmission type according to which a communication is executed using a competition period for determining priorities of the subscriber data, a reservation period for making a reservation for time slots for use in transmission of the subscriber data, and an assignment period for assigning a memory period according to an amount of the

Abstract: A digital audio signal processing and distribution sub-assembly unit, plug compatible or integratable with single user digital radios, for audio channels and simultaneous re-transmission to multiple user headsetss. The sub-assembly will enable multiple users to select individual channels for listening, via audio headsets, from satellite digital radio broadcasts, which will encompass up to 100 channels of music and talk show programming. Headsets will have either direct wire connections to the digital radio receiver (via a jack connection), or infra-red (IR) links or RF links, which can allow the user to roam significant distances from the radio without the encumbrance of a wire link. The unit will function in automobiles or in homes, with auto usage eventually implemented with interior wiring with access jacks for the headsets built into doors and dashboards.

Abstract: In a medium access control (MAC) protocol for a wireless communications network, communications between a control point and other nodes are coordinated by a repeated superframe. This superframe contains in sequence a contention-free period (CFP1), a contention-based period, and second contention-free period (CFP2). Prior to CFP1 a node hops from one channel frequency to another. CFP2 in a superframe is used for initial transmission of isochronous data (such as voice signals); CFP1 of the following superframe is used for retransmission of any such data which were not correctly received at the first attempt, after the frequency hop at the start of that following superframe. This arrangement minimises delay before retransmission of data, and improves the robustness of the system.

Abstract: A flexible channel architecture supports full-duplex, radio-frequency communication between a base station, such as a PWT or DECT base station, and a group of remote terminals. Communication from the base to the terminals is by way of a radio-frequency carrier having a first frequency, and communication from the terminals to the base is by way of a second radio-frequency carrier having a second frequency. Each carrier is organized to provide an N-timeslot time-division multiple access data stream (N an integer), so that together the two carriers provide a 2N-timeslot system. Within each data frame, data from the base to the terminals is sent on the first carrier during a first half of the frame, and data from the terminals to the base is sent on the second carrier during the remaining half of the frame.

Abstract: Method and apparatus for two-user join demodulation in a system having transmit diversity. A receiver includes at least a detector unit and a channel estimation unit, and exploits transmit diversity employed by at least one of two users or transmitters on a channel. Symbol detection and channel estimation are performed in block or batch fashion, or recursively on a symbol-by-symbol basis. Joint detection makes use of transmit diversity by at least one of the transmitting users. Channel estimates can be updated using channel tracking. If the signals from the first user and the second user are asynchronous, detection can be accomplished in part through reference to a pulse-shape component. The receiver may be incorporated into a mobile communication terminal.

Abstract: An ADSL system for operating in a time duplex system that provides alternative configurations for limiting crosstalk in a broadband network is disclosed. The ADSL system introduces a trial bitmap profile configuration to maximize the bit rate at which information is transmitted, regardless of network topology. In a simplified embodiment, a composite signal to noise ratio is derived from a minimum far end crosstalk signal to noise ratio and a minimum near end crosstalk signal to noise ratio. A maximum bit rate for the transfer of information, which is directly related to the derived composite SNR, is then determined. Information is then transmitted simultaneously between an asymmetric digital subscriber line central office and an asymmetric digital subscriber line customer premise at the determined maximum bit rate.

Abstract: A method of communicating through a passive optical network (PON) that improves the efficiency of the network with low cost child apparatuses having only simple functions. A parent apparatus provides the child apparatuses with a multi-frame standard signal, and a child apparatus transfers asynchronous information as a frame of variable length, as it is, at a time delayed from the multi-frame standard signal by a time period designated by the parent apparatus. Since the asynchronous information does not need to be divided into pieces to which a frame header is attached, the efficiency of the uplink channel is increased.

Abstract: A communication system based upon frequency-domain MIMO processing is disclosed. A transmitting device of the communication system transforms time-domain signals into frequency-domain signals, and weights each frequency-domain signal to form weighted frequency-domain signals with each weighted frequency-domain signal being a function of each frequency-domain signal. The transmitting device transmits weighted time-domain waveforms as a function of the weighted frequency-domain signals. In response thereto, a receiving device of the communication system provides frequency-domain samples that are a function of the one or more weighted time-domain waveforms and weights each frequency-domain sample to form one or more weighted frequency-domain samples with each weighted frequency-domain sample being a function of each frequency-domain sample. The receiving device decodes the weighted frequency-domain sample to obtain the information represented by the time-domain signals.

Abstract: A telecommunications system provides telephone services to subscriber locations over dedicated optical fibers which extend in a “star” configuration from a telephone central office. A transmultiplexer installed at the central office is connected between a digital switch and the optical fibers. The transmultiplexer has a plurality of FDM ports, each of which is connected to a respective one of the optical fibers. The transmultiplexer is connected by one or more TDM ports to the digital switch. Preferably, the transmultiplexer provides a concentrating function whereby the number of subscriber lines served by the transmultiplexer is greater than the total voice-grade channel capacity of the connection between the transmultiplexer and the digital switch.

Abstract: The present invention relates to a transmission method and a transmission apparatus for transmitting signals on the basis of a OFDM/TDMA-system, wherein a plurality of subcarriers being orthogonal to each other are allocated to a variable number of channels, each channel containing a variable number of subcarriers depending on information to be transmitted in said signals, wherein, for the transmission of said signals in a GSM-system having a constant number of predetermined GSM-frequency channels and a constant number of predetermined GSM-timeslots being grouped in GSM-frames, the number of said subcarriers is allocated corresponding to the bandwidth of said GSM-frequency channels, so that a multiple of one resulting OFDM/TDMA-timeslot matches with one or a multiple of one GSM-timeslots, wherein a pilot symbol is allocated to every n-th subcarrier in said GSM-frequency-channels, whereby n is an integer and>1, and wherein said signals are transmitted.

Abstract: A power control bit inserting method between a base station and a terminal. The base station and the terminal each use a plurality of adjacent frequency bands as signal paths with independent signal paths of a real part and an imaginary part given to each frequency. In the power control bit inserting method, a unit time is set to a power control group period, n-bit data is allocated to each signal path, the power control group period is divided by the number of signal paths, and a power control bit is inserted in each divided segment, so that the insertion positions in the real and imaginary parts of each frequency are spaced from each other by n/2 bit and the start position of the real signal path of each frequency is inserted at an appointed bit position of the corresponding frequency.

Abstract: A terminal in a wireless telephone system can efficiently search for available base stations. Communication of user information between a base station and a terminal is intermittently performed in a predetermined time slot period. The transmission and reception of user information at the terminal are stopped at once in a plurality of predetermined time slot periods in such intermittent communication. The cell search for receiving a frequency channel in which control information is transmitted from the base station is performed, so that available base stations are searched. The number of cell search periods can be increased or decreased from time to time.

Abstract: A method of the present invention includes the steps of identifying (801) a first frequency allocation and a second frequency allocation and programming a radio frequency device (401, 701, 901) to at least one of: a) simultaneously receive a first signal within the first frequency allocation and a second signal within the second frequency allocation; and b) simultaneously transmit a first signal within the first frequency allocation and a second signal within the second frequency allocation.

Abstract: A network utilizing two or more wiring systems with a bridging function to provide a signal interconnect for communication within and between wiring systems. The bridging function can translate the network signals to a different frequency.

Abstract: A radio communication system is formed of a plurality of radio communication terminals and a radio communication control terminal for controlling radio communication. Data communication is performed between each radio communication terminal and the radio communication control terminal by the orthogonal frequency division multiplexing (OFDM) method. Data is multiplexed with a frame structure having the specified number of symbols by the TDMA method. The radio communication control terminal transmits a synchronization acquisition code to the plurality of radio communication terminals in each frame. Each radio communication terminal receives the synchronization acquisition code, sets a timer according to the receiving timing of the synchronization acquisition code, and sets the transmission timing and the receiving timing with the timer being used as the reference. With the use of the OFDM method, demodulation is performed without an error even if jitter occurs.

Abstract: A method of, and apparatus for, processing interference in a cellular communications system. The method includes the steps of determining a quality value per burst; identifying those bursts for which the quality value is below a predetermined threshold; determining a pattern of the identified bursts in terms of transmission frequency and time; calculating respective predicted patterns based on respective hopping determination parameters of other cells and of the given cell; comparing the determined pattern of the identified bursts with the predicted patterns; and responsive thereto predicting the hopping determination parameters of whichever interfering cell produced the determined pattern of the identified bursts by interfering with the given cell. Further possibilities include comparing the given cell with the interfering cell and identifying predicted interfering timeslots. Further interference can be reduced by not transmitting bursts during some or all of the predicted interfering timeslots.

Abstract: A dual-band receiver for a wireless communication device having multi-slot capability. A first oscillator generates a relatively high frequency traffic LO signal. A second oscillator generates a first relatively low frequency signal, and a third oscillator generates a fixed low frequency signal. A first mixer mixes the first and fixed low frequency signals to produce a relatively high frequency monitor LO signal. A switch selects the traffic LO signal when the receiver is in a traffic slot and the monitor LO signal when the receiver is in a monitor slot. The selected LO signal is provided to a second mixer along with the received signal to produce a first IF signal. A third mixer mixes the first IF signal and the fixed frequency signal to produce an output signal.

Abstract: A physical layer device (PHY) device in a home LAN employs discrete multitone technology (DMT). The DMT system enables usage of existing residential wiring, which typically is telephone system grade twisted copper pair. The PHY device comprises an analog front end (AFE) circuit that frequency shifts the spectral images by using a clock signal. The multiplication of the clock signal is accomplished using a digital mixer or, in the alternative, an analog switch.

Abstract: In one aspect of the invention, an OFDM receiver for receiving and demodulating OFDM signal comprises an automatic gain adjuster for adjusting the level of OFDM signal; a demodulator for demodulating a level-adjusted signal outputted from the automatic gain adjuster; a detector for detecting guard intervals contained in the OFDM signal; and a controller for controlling the automatic gain adjuster within the periods of guard intervals detected by the detector. In another aspect of the invention, an OFDM receiver includes a detector for detecting a level change of an OFDM signal and an automatic gain controller for adjusting the level of the OFDM signal in accordance with a signal level detected by the detector.

Abstract: Disclosed is a system and method to provide continuity of service in a radio broadcasting system comprising at least one modem using the COFDM technique, comprising the transmission of N time-frequency cells modulated independently of one another.

Abstract: Two related voiceband compression techniques are employed in order to enable an RF telecommunications system to accommodate data signals of high speed voiceband modems and FAX machines. A High Speed Codec enables the telecommunications system to pass voiceband modem and FAX transmissions at up to 9.6 kb/s. An Ultra-High Speed Codec supports voiceband modem and FAX transmissions up to 14.4 kb/s. The High Speed Codec operates using three 16-phase RF slots or four 8-phase RF slots, and the Ultra-High Speed Codec operates using four 16-phase RF slots. Because these codecs transmit information over several RF slots which can be contiguous, the slots within RF communication channels are dynamically allocated. The Dynamic Timeslot/Bandwidth Allocation feature detects and monitors the data transmission and forms a data channel from the necessary number of slots.

Abstract: A wireless, cellular radio link is provided from a base station to a plurality of subscriber stations within a cell reception area. Information data, which may be of textual, video or other format, are communicated asymmetrically as high bandwidth transmissions in the downstream direction to the users while low upstream bandwidth is provided to permit users to request the data or to provide return radio link condition information. Buffers associated with respective subscribers collect requested data from information providers for transmission by the base station in a statistical time division multiplexed (STDM) fashion, whereby each subscriber may be assigned a minimum transmission time interval during which data will be transferred from the associated buffer. Controlled logical token passing governs a variable token interval during which data transmission for each buffer is permitted in turn.

Abstract: A wireless communication system combines time and space diversity to reduce fading and simplify receiver design. In particular, a data packet which carries digital telephone traffic, is transmitted at three different times from three different antennas. The mobile subscriber receiver thus receives the same data packet at three different times from three different antennas, and uses the best data packet or combination of the data packets to reduce the effects of fading. A transfer station receives a time division multiplex multiple access (TDMA) signal from a base station carrying telephone data packet traffic to form three data packet repeats at spatially diverse antennas locations. The transfer station further modulates a code division multiple access (CDMA) system using a TDMA signal which links the mobile subscriber receiver to the transfer station. Each data packet received at the transfer station is thus retransmitted at three different times to the mobile subscriber station on a CDMA link.

Abstract: A method and apparatus for carrying out synchronous co-division multiple access (SCDMA) communication of multiple channels of digital data over a shared transmission media such as a cable television system coaxial cable, a fiber optic or copper conductor telephone link, terrestial microwave, satellite link, local or wide area network, wireless including cellur network or some combination of these media using suitable interface circuitry. The system includes modems at remote units and a central unit to receive time division multiplexed digital data arranged into timeslots or channels and uses orthogonal codes to encode each channel of multiple data and spread the energy of each channel data over a frame of data transmitted in the code domain. Spreading the data this way makes the system less susceptible to impulse noise.

Abstract: A frequency carrier allocating method is provided which can effectively utilize frequency carriers when the traffic of the uplink is asymmetric to that of the downlink in the FDD cellular system. Plural frequency carriers are arranged in each of two frequency bands FB1 and FB2. Base stations are divided into two groups BSG1 and BSG2. In the group BSG1, frequency carriers in the frequency band FB1 are allocated to the downlink of a base station while frequency carriers in the frequency band FB2 are allocated to the uplink thereof. In the group BSG2, frequency carriers in the frequency band FB2 are allocated to the downlink of a base station while frequency carriers in the frequency band FB1 are allocated to the uplink thereof. Bi-directional communication is performed between the base station and a mobile station using the frequency of the frequency carrier.

Abstract: A digital telephone system for processing a plurality of information signals received in parallel over telephone lines from a public network exchange which are then transmitted in parallel over a plurality of radio frequency (RF) channels to a plurality of mobile subscriber units, each capable of receiving on any of those RF channels, includes an exchange, signal compressors, a multiplexer, a transmitter and a central processing unit. The central processing unit is responsive to a received connection request signal by providing an assignment signal indicating a slot and an RF channel to be used for the respective information signal. The central processing unit maintains a memory of which slots and which RF channels are so assigned and consults the memory upon receipt of the connection request signal and then provides the assignment signal that establishes the utilization of one of the slots at one of the RF channels that is not assigned to another information signal.

Abstract: A channel assigning method and a communication apparatus for executing appropriate channel assignment in a mobile communication system when both a channel for a service area based on a FDD method and a channel for a service area based on a TDD method can be assigned are provided. For example, if both a channel for a service area based on a CDMA-FDD method and channels for service areas based on a CDMA-TDD method can be assigned to a request for channel assignment, and a handover frequency of the mobile station related to the request is high, the channel for the service area based on the CDMA-FDD method is assigned.

Abstract: The present invention relates to a high-speed digital transmission method using an analog subscriber line (for example, an existing telephone-use copper cable), a subscriber accommodating system used in the high-speed digital transmission method, an accommodating device on a subscriber-terminal side and an accommodating device on an accommodating station side. The present invention includes the steps of providing a subscriber distributing device, to which a plurality of subscribers are connected, on a subscriber-terminal side of an analog subscriber line in a high-speed digital transmission method using the analog subscriber line; setting a low-frequency band part as a control channel; setting a high-frequency band part as one or a plurality of communication channels; and controlling the one or plurality of communication channels by use of the control channel. The plurality of subscribers communicate by using the same analog subscriber line.

Abstract: A method of frequency hopping is supported by a basestation having a broadband transceiver. The method permits changing physical channels upon which mobile subscribers communicate with the basestation, wherein the broadband transceiver is operated using static transceiver frequencies, the method exclusive of switching communication signals between transceivers. In one embodiment, the method maps baseband output signals from a digital channelizer which represent physical channels to ones of digital signal processors representing logical channels and baseband input signals of a digital combiner to ones of logical outputs of digital signal processors according to a mapping signal.

Abstract: A system for rapidly acquiring a time reference for the location determination of a wireless communication device. The system includes a wireless communication device (200), a GPS satellite (202) and a communication satellite (208). The method comprises the steps of acquiring a communication satellite signal (210) and using the finite frame time to establish a course time reference. Once the course time reference is established, an absolute device time is determined by the wireless communication device, which as a result is synchronized to the absolute time of the communication satellite (208) to within ten milliseconds. The absolute device time is then used to synchronize the GPS portion of the wireless communication device with the GPS satellite system.

Abstract: A time division multiplexed communications method and system in which time is divided into a number of frames and each frame is divided into N data bursts. The method and system further has a first multiplexer by which a half rate channel is formed as a series of bursts that occur periodically every N bursts once per frame, a second multiplexer in which a full rate channel is formed as two half rate channels on consecutive timeslots, and a transmitter transmitting the full rate channel from a first wireless station to a second wireless station. The full rate channel provided by two half rate channels on consecutive timeslots yields a significantly larger resource pool available for assignment of communication traffic. For full rate channels, the interleaving 0246/1357 method that is used by the system is just as good as the known 0123/4567 method when ideal frequency hopping is used, and the 0246/1357 method performs better when non-ideal frequency hopping or no frequency hopping is used.

Abstract: A multiplexing apparatus and method, a transmitting apparatus and method, and a recording medium arranged to prevent a delay of one of multiplexing scheduling processing and multiplexing processing in accordance with a schedule obtained by the multiplexing scheduling processing from influencing the other of these processings. A scheduler calculates schedule information on the basis of access unit information from an encoder and stores the calculated schedule information by supplying it to an intermediate buffer. If some additional data is to be multiplexed, the scheduler also calculates the additional data and stores the calculated additional data by supplying it to an intermediate buffer. A bit stream multiplexer reads out schedule information from the schedule information intermediate buffer, selects data designated by the schedule information from an elementary stream from the encoder and from additional data stored in the additional data intermediate buffer, and outputs the data as a multiplexed stream.

Abstract: An asymmetrical network for coupling customer-premises Internet hosts such as personal computers to the Internet. The head end of a CATV system has a high-bandwidth connection to the Internet. The down link connecting the personal computers to the Internet is the cables provided by the CATV system; the up link is a telephone connection to the head end. A router is connected to the down link by means of a RF modem, to the up link by means of an analog modem, and to a LAN which is connected to the Pcs. The router routes IP packets for the hosts that are received on the CATV cable to the hosts via the LAN; it routes IP packets from the hosts that are destined for the Internet to the head end via the telephone line. The asymmetrical network conserves IP addresses and addresses on the CATV cable by dynamically allocating the IP addresses for an RF modem's hosts and an address on the CATV cable for the RF modem in response to a request made by the RF modem via the telephone line.

Abstract: The invention relates to a synchronous TDD system for the transmission of speech and/or data between a master unit (FP) and at least two slave units (PP1, PP2) which are associated with the master unit (FP), and also to a method to be carried out by such a system. In order to enable direct communication between the slave units (PP1, PP2) of the same system despite the regular transmission of synchronization signals to the slave units (PP1, PP2) by the master unit (FP), according to the invention the slave units (PP1, PP2) are rendered ready to receive in fixed time slots in a frequency channel which is not used by the master unit (FP) in these time slots. In these time slots the slave units (PP1, PP2) can receive signals from other slave units (PP1, PP2) of the system in order to initiate a communication between themselves.

Abstract: The invention concerns a multicarrier signal designed to be transmitted to digital receivers, especially in a non-stationary transmission channel, corresponding to the frequency multiplexing of several elementary carriers each corresponding to a series of symbols, two consecutive symbols being separated by a symbol time &tgr;0, a signal in which, firstly, the spacing &ngr;0 between two neighboring carriers is equal to half of the reverse of the symbol time &tgr;0 and, secondly, each carrier undergoes an operation of filtering for the shaping of its spectrum having a bandwidth strictly greater than twice said spacing between carriers &ngr;0 and is spectrum is chosen so that each symbol element is highly concentrated in the temporal domain and in the frequency domain. The invention also concerns the methods for the transmission and reception of such a signal.

Abstract: In the radio transmission method according to the invention, which operates with a mixed frequency and time division multiplex method FDMA/TDMA, in which a relatively broad frequency band is divided according to the FDMA method into a plurality of carrier frequency ranges, namely the so-called main channels, and a plurality of time slots, namely the so-called sub-channels, distributed in a frame structure, are formed on each carrier frequency level according to the TDMA method, a grouping, that is to say a so-called cluster, of subscriber stations is assigned a limited number of main channels. A main channel signal is divided into one or more sub-channel signals which are associated with a cluster and which are transmitted using the TDMA method.

Abstract: The key of the invention is to introduce an interoperability device in a communication system which integrates an IEEE 802.11 transceiver and a Bluetooth transceiver. The device prevents that one transceiver is transmitting while the other is receiving, which would cause interference at the receiving transceiver. In addition, the device preferably prevents that both systems are transmitting at the same time to avoid interference at the receiving device(s). Optionally the device prohibits simultaneous reception of both transceivers. In that way the radio receiver can be shared between the devices, allowing a cheaper and smaller hardware design.

Abstract: A system and method for modifying symbol duration for the efficient transmission of information in a time duplex noise environment is disclosed. In a simplified embodiment, the system modifies the length of Discrete MultiTone (DMT) symbols, thereby providing a system wherein a first half of the DMT symbols are transmitted entirely during a period in which there is far end crosstalk (FEXT) noise, and a second half of the DMT symbols are transmitted entirely during a period in which there is near end crosstalk (NEXT) noise. Preferably, the duration of each DMT symbol is selected to be 0.25 ms such that exactly ten DMT symbols fall within a time duplex period of 2.5 ms. As such, during a FEXT period, exactly five DMT symbols are transmitted, and during a NEXT period, exactly five DMT symbols are transmitted. Therefore, in each TTR period, an additional DMT symbol, with modified length, is transmitted during the FEXT period, during which information is transmitted at a high bit rate.