Abstract: An apparatus in a wideband radio transceiver for mitigating interference between a wideband radio operating in a wide frequency band and a narrowband radio operating in a narrow frequency band within the wide frequency band. The effects of transmissions by the wideband radio on the narrowband radio are reduced by creating by the wideband radio, a transmitter notch of decreased transmit power centered at a frequency in the wide frequency band that is fixed in relation to the wideband carrier frequency. The wideband carrier frequency is then adjusted so that the transmitter notch is aligned with the second radio's narrow frequency band. The effects of transmissions by the narrowband radio on the wideband radio are reduced by creating by the wideband radio, a fixed receiver notch of decreased receiver gain in the wideband receiver, and aligning the narrowband signal with the fixed receiver notch.

Abstract: In a communication network having a plurality of units and a distributed MAC protocol, wherein data is exchanged between units during at least some of the time slots in a succession of time slots, a method is provided for establishing a desired network configuration. The method includes the step of designating one of the units as a supervisory unit and the other units as non-supervisory units. Certain of the time slots are designated as supervisory priority slots. All of the non-supervisory units are required to monitor transmissions from the supervisory unit during each of the supervisory priority slots, and the supervisory unit is operated to transmit an instruction establishing the desired network configuration only during one of the supervisory priority slots.

Abstract: Transmitter and receiver functionality are separated in dual-mode radio transceivers to support high-rate services. Transceivers with highly asymmetric requirements that need only a high-rate transmission or only high-rate reception functionality are supported by including a high-rate transmitter to support pushing data out or a high-rate receiver to support pulling data into the transceiver at high data rates.

Abstract: A method and apparatus for managing traffic in a network to and from a remote communications device with limited power supply resources. A controller determines the existing power level of the device and uses the determination to control data transmission to and from the device. Data may be transmitted and received by the device by determining the power required to complete a transmission or reception. The controller then determines whether to send the data, redirect the data, cancel the data transmission, or transmit only a portion of the data. The decision is made as to which option to choose based on the amount of power available to complete the data transmission.

Abstract: A mobile station is operated in a telecommunications system that includes a base station and one or more relay stations. The mobile station communicates directly with the base station via a first channel. To facilitate selection of a suitable relay station, the mobile station broadcasts a burst for receipt by a plurality of relay stations. Relay stations each measure a quality of the received burst and communicate this information to the base station, which uses the information to select a most suitable one of the relay stations for use in carrying on indirect communications between the base station and the mobile station.

Abstract: Method and apparatus for dynamically selecting a packet type based on the quality estimates of the channel are disclosed. From these channel quality estimates, specific properties of the packet may be selected including whether a coding scheme should be used, the packet length, and the modulation used. The packet type selection is then performed in a dynamic fashion based on updates or changes to the channel conditions.

Abstract: An entire radio transceiver can be completely integrated into one IC chip. In order to integrate the IF filters on the chip, a heterodyne architecture with a low IF is used. A single, directly modulated VCO is used for both up-conversion during transmission, and down-conversion during reception. Bond-wires are used as resonators in the oscillator tank for the VCO. A TDD scheme is used in the air interface to eliminate cross-talk or leakage. A Gaussian-shaped binary FSK modulation scheme is used to provide a number of other implementation advantages.

Abstract: A carrier frequency is selected to be used to communicate information to a transceiver in a communication system. Selecting includes, on each of one or more carrier frequencies, transmitting a probe message to the transceiver. A frequency offset between any two adjacent ones of the carrier frequencies is at least about 8 MHz. One or more response messages are received from the transceiver, wherein each of the one or more response messages is a response to a received one of the one or more probe messages. The one or more response messages are used to determine which of the one or more carrier frequencies will be used to communicate information to the transceiver. In some embodiments, each of the probe messages includes a training sequence, and information included in the one or more response messages enables selection of one of a number of possible modulation schemes to be used.

Abstract: A terminal that is capable of communicating on a first system that is an ad-hoc communication system, and a second system that is a mobile communication system is operated by receiving one or more dynamically changing values from a network part of the second system; and using the one or more dynamically changing values to determine one or more parameters that characterize one or more ad-hoc communication operations in the first system. The ad-hoc communication operations may, for example, be an inquiry operation, a paging operation, and a scanning operation. The one or more parameters that characterize these operations may include when the operation will occur, and on what frequency it will be carried out. The dynamically changing values may include a clock value and/or a frame counter value. In this way, timing and/or frequency uncertainty may be eliminated when performing the operations in the first system.

Abstract: A channel response of a channel in a dual-mode radio communication system is determined by detecting a wideband signal and using a narrowband receiver to generate received signal strength measurements at frequencies located within a bandwidth of the wideband signal. The wideband signal need not be intended for reception by the radio unit that detected it and generated the received signal strength measurements therefrom. The received signal strength measurements are used as an indicator of the channel response of the channel. Based on the indicator of the channel response, a modulation scheme may be selected. The indicator of the channel response of the channel may also be used to determine an adjustment of a center frequency of the wideband signal.

Abstract: Method, apparatus, and system for synchronization in radio communication systems are presented. The method includes the steps of encapsulating symbols in an information stream then modulating the stream. The modulated information stream is then sent over a communication channel at a first robustness level, and the level of robustness of the information stream is then reduced to a second robustness level according to a predetermined function. The modulated information stream is received from the communication channel. The information stream is then demodulated after a first number of symbols have been received, wherein the first number of symbols is less than a second number of symbols that would have to be received to demodulate a corresponding information stream sent over the communication channel only at the second robustness level.

Abstract: A dual-radio communication apparatus has a first radio device, such as a Bluetooth radio, for use in a first frequency band, and a second radio device, such as a Globalstar satellite radio, for use in a second frequency band, which is proximate to the first frequency band. The communication apparatus also has a controller coupled to the first and second radio devices. The first radio device may comprise a frequency-hopping spread-spectrum transmitter. Moreover, the first radio device has a first operating mode employing a first frequency range. The first radio device also has a second operating mode employing a second frequency range, which is smaller than the first frequency range. The controller is adapted to set the first radio device in its second operating mode, when the second radio device is in operation, and otherwise set the first radio device in its first operating mode.

Abstract: A supplied analog signal is modulated by comparing the supplied analog signal with a noise signal. As a result of each comparison, an output signal is generated having a first value if the supplied analog signal is greater than the noise signal and generating an output signal having a second value if the supplied analog signal is lower than the noise signal. Such modulation is useful in applications such as analog-to-digital conversion. The transfer function of the modulator is a function of the distribution of the noise source.

Abstract: A system, method, and computer program product for allocating resources to a communication channel between a transmitter and a receiver are disclosed. The receiver implements a procedure that instructs the transmitter to utilize the maximum available bandwidth, consistent with maintaining satisfactory communication channel performance. When the performance of the communication channel degrades, the receiver measures the strength of a communication signal received from the transmitter. If the communication signal strength satisfies a threshold, then the bandwidth dedicated to the communication channel may be decreased, and at least one of the number of bits per symbol and coding rate may be increased. By contrast, if the communication signal strength fails to satisfy a threshold, then the transmitter may increase the transmission power and/or reduce the user rate of the communication link.

Abstract: A transceiver operates in a communication environment capable of including other transceivers, wherein the transceiver sends and receives traffic in accordance with a first communications standard, and other transceivers send and receive traffic in accordance with other communication standards that are incompatible with the first communications standard such that traffic sent in accordance with any of the first and other communications standards cannot be received by a receiver operating in accordance with any other one of the first and other communications standards. The transceiver identifies a carrier frequency for use as a shared broadcast channel that is accessible by the transceiver and by the other transceivers, and broadcasts information on the shared broadcast channel, wherein the information informs the other transceivers of the presence of the transceiver.

Abstract: Systems and methods for providing access to a time-slotted communication channel are disclosed. Access to the channel is granted by possession of a pseudo-token transmitted between communication units with packets, such that the recipient of a data packet receives the pseudo-token with the packet. Communication units may be assigned reserved slots during which the pseudo-token automatically is assigned to the communication unit. Further, communication units may be assigned priority levels according to which contention contests may be resolved. Reserved slots and priority rankings may used in combination to accommodate varying levels of QoS required or requested by communication units on the channel.

Abstract: Method and apparatus for transferring a plurality of messages over a common information carrying medium, each message having at least one segment, are provided. A message lifetime is defined for each of the respective messages. A respective segment number is then assigned to each segment of a same message in order of a predefined sequence of segment numbers, the segment number defining a position of a corresponding segment within the same message. In addition, a respective message number is assigned to each of the messages in order of a predefined sequence of message numbers, each message number being assigned to at least one segment of a same message. Finally, at least one segment of each respective message is transmitted over the medium at least once having any assigned segment and message numbers included therein until the message lifetime associated with the respective message expires.

Abstract: A system and method for training a radio receiver to mitigate the effects of ISI caused by multi-path includes receiving a header of a transmitted packet at the receiver, the header containing at least one flag to identify a corresponding reference training sequence to be selected by the receiver and to indicate whether a training sequence is inserted in a packet. The receiver decodes the header to determine whether a training sequence is indicated by the flag and to select the corresponding reference training sequence. The training sequence is transmitted positioned within a data packet at a midamble between the header and a first segment of the data packet. The received training sequence is compared with the selected reference training sequence and the equalization parameters of the receiver are adjusted based on the results of the comparison. The selected reference training sequence corresponds to the modulation scheme applied to the payload.

Abstract: Whether to indicate reception of an access code in a receiver operating in a communications system is determined by receiving a signal and generating a correlation value by correlating the received signal with a reference code. A threshold level is set to a first value if the receiver is in a scan mode. The threshold level is set to a second value if the receiver is in a traffic mode, wherein the second value corresponds to a lower degree of correlation than the first value. The correlation value is compared with the threshold level. Reception of the access code is indicated only if the correlation value compares favorably with the threshold level.

Abstract: An access scheme in a communication system can deal with a mix of devices having different power constraints and different latency requirements and allow highly asymmetric latency behavior. Such a communication system may include a central control station that broadcasts beacon messages on a communication channel, such as a radio channel, and at least one remote terminal that accesses a communication channel based on the beacon messages. The beacon messages are configured such that individual access to the communication channel by each terminal is controlled according to a grouping of the terminals into respective beacon groups. Each beacon group may have a corresponding beacon message, and beacon messages corresponding to different beacon groups may be broadcast at staggered time intervals.