Abstract: A characteristic is measured on multiple portions of an integrated circuit, and the supply voltage adjusted based on the measurements. In an embodiment, the characteristic corresponds to propagation delay which indicates whether the integrated circuit is implemented with a strong, weak or nominal process corner. In general, the supply voltage can be increased in the case of a weak process corner and decreased in the case of a strong process corner.

Abstract: In one aspect, the present invention provides a system and method for selecting precursor equalizer coefficients and a serializer deserializer (SERDES) incorporating the system or the method. In one embodiment, the system includes: (1) a cost definer configured to generate an eye height cost function based on continuous-time channel and crosstalk symbol responses pertaining to a particular serial link and (2) a cost evaluator associated with the cost definer and configured to evaluate the eye height cost function based on a particular criterion thereby to produce coefficients for a precursor equalizer to be applied with respect to the particular serial link.

Abstract: A phase-locked loop (PLL) architecture (100) is provided that includes a voltage-controlled oscillator (VCO) (116). The PLL architecture (100) also includes a digital calibration loop (132) coupled to the VCO (116). The digital calibration loop (132) implements a digital filter (126) to provide a digital control to the VCO (116) for centering a VCO frequency output. The PLL architecture (100) also includes an analog calibration loop (130) coupled to the VCO (116). The analog calibration loop (130) provides an analog control to the VCO (116) for adjusting the centered VCO frequency output.

Abstract: A communication system 10 initialized using an iterative training portion is disclosed. The communication system 10 comprises a first transceiver 12 operable to communicate according to a digital subscriber line standard and a second transceiver 14 operable to communicate according to the digital subscriber line standard with the first transceiver 12. The first and the second transceivers 12, 14 are operable to perform an initialization 50, including a handshake portion 52, a channel analysis portion 56, and a training portion 54, the first and second transceivers 12, 14 negotiating a plurality of iterations of the training portion 54.

Abstract: The present invention discloses a transmitter and receiver for use with an orthogonal frequency division multiplexing (OFDM) communications system. In one embodiment, the OFDM communications system includes an OFDM transmitter that generates a training sequence that includes a fractional tone in a guard band thereof and transmits the training sequence via a channel. The OFDM communications system further includes an OFDM receiver that receives the training sequence and employs the fractional tone to obtain a channel response estimate.

Abstract: A digital device 310 with a plurality of collocated wireless networks encounters inter-network interference if the collocated wireless networks operate in a common operating frequency. A coordinator unit 510, coupled to the plurality of wireless networks, provides a transmission reservation system wherein a wireless network with a need to transmit can request and receive a reservation for time to transmit. The coordinator unit 510 provides a way to schedule transmissions from the plurality of wireless networks and to reduce the probability of collisions.

Abstract: The invention provides systems, devices, and methods for frequency hopping. In one method embodiment, the invention hops between frequencies by using the same channel to transmit data from a master to a slave, and from the slave to the master. One system embodiment provides an enhanced master coupled to an enhanced slave. In one device embodiment, the invention is a computer readable medium adapted to enable frequency hopping in a frequency band.

Abstract: Various antenna designs that are small and cost effective are disclosed. In one design, the antenna is a bent and folded monopole antenna. In another design, the antenna is a folded and tapped monopole antenna. In yet another design, the antenna is a folded, bent, and tapped monopole antenna. The antennas may be part of a system using two back-to-back symmetric antennas. The antennas may be part of a modem, such as a wireless computer modem or a wireless handset.

Abstract: A semi-distributed method of managing the spectral power over multiple digital subscriber line communication loops (LP1, LP2) is disclosed. A central office (CO) DSL transceiver (10) and a remote terminal (RT) DSL transceiver (15) communicate with customer premises equipment (CPE) (121, 122) over separate twisted-pair wire loops (LP1, LP2) that are in sufficient physical proximity with one another as to suffer from crosstalk. A network management center (NMC) (20) initializes a price parameter, which is used by the CO (10) and RT (15) in independent maximization problems. The CO (10) derives a maximum tolerable power spectral density for the RT (15) that permits the CO (10) to reach a target data rate, and the RT (15) derives an actual power spectral density that maximizes its data rate, each using the price parameter. The NMC (20) compares the actual RT power spectral density to the tolerable RT power spectral density, and adjusts the price parameter accordingly, with the process repeating until convergence.

Abstract: Systems and methods for automatic gain control are disclosed. In one aspect of the invention, a system is provided that comprises a programmable gain amplifier that amplifies an input signal based on a gain signal. The system further comprises an analog-to-digital converter that generates at least one digital output signal from the amplified input signal, and an automatic gain control component that determines an adjustment of the gain signal based on a comparison of the at least one digital output signal to a predetermined maximum amplitude reference level.

Abstract: An efficient method of generating a bit-reverse index array in real time without performing any bit manipulation for a wireless communication system.

Abstract: A method of communicating data across a channel that experiences near-end cross talk (NEXT) interference and far-end cross talk (FEXT) interference in alternate intervals. In one embodiment, the method comprises: a) determining NF, the number of bits per symbol usable in a FEXT-only mode of operation; b) determining NS, a number of bits per symbol usable in a single mode of operation; c) determining whether the FEXT-only mode or the single mode provides a higher data rate; and d) configuring a modem to transmit using the mode having a higher data rate. The FEXT-only mode may be determined to have a higher data rate when 126NF>340NS.

Abstract: The present invention provides an FFT/IFFT processor for use with N data values. In one embodiment, the FFT/IFFT processor includes an even-odd data mapper configured to provide a mapping of the N data values into N/2 mapped complex data values if the N data values are real. Additionally, the FFT/IFFT processor also includes a separator-combiner, coupled to the even-odd data mapper, configured to compute either an FFT based on the mapping or an IFFT based on the N data values if the N data values are complex.

Abstract: An unconnected power save method reduces the battery consumption of a wireless station in a wireless local area network (WLAN). A wireless station enters a sleep mode between scans for a prospective access point. The sleep duration time is determined using the current position of the station relative to the WLAN network topology.

Abstract: An enhanced services display message protocol (ESDMP) facilitates display of messages in a compliant analog telephony device (ATD). An exemplary gateway device in a voice over packet (VOP) network can activate enhanced services in a compliant ATD using the ESDMP and includes a controller and first and second interfaces. One of the interfaces can transmit and receive communications over a VOP network. The other interface can transmit and receive voice band message data modulated according to a frequency shift keying (FSK) protocol. The ESDMP can be used to configure the gateway to activate features supported by the ATD, to update call state information and to display feature state information.

Abstract: A low power packet detector (LPPD) can significantly reduce the average power consumption of WLAN devices. The LPPD takes advantages of 802.11 protocols to turn on and off selected modules of an 802.11 receiver based on the packets on the medium and the decoding stages. The LPPD can be implemented mostly in firmware with minor hardware modifications to existing chips or be implemented in ASIC technology that takes full advantages of the power saving made possible by it.

Abstract: The present invention provides a system for controlling isochronous data admission, within a WLAN system (102) that transports both isochronous and asynchronous data. The system includes an apparatus (300), functioning as an access point within a WLAN system. The apparatus comprises a memory (306) and a transceiver (312) communicatively coupled to the memory. The apparatus further comprises an access coordinator (302), communicatively coupled to the memory, and adapted to: evaluate actual access times of previous isochronous data streams, to determine projected access times needed by a new isochronous data stream, and to decide to admit or reject the new isochronous data stream based on an evaluation of the actual and projected access times.

Abstract: Multicarrier modulated communications, involving a transmitting modem (30; 30?) and a receiving modem (40; 40?) that operate according to normal operating mode and a low-power, quiescent, mode, are disclosed. In the quiescent mode, transmitter power is saved by scaling down the amplitude of the transmitted symbols in each frame by a scaling factor (A), and transmitting multiple instances of the frames in sequence. On receipt, the repeated frames are summed, and the summed amplitudes scaled to account for the repetition factor (M) and the scaling factor (A), to recover the transmitted information. If the repetition factor (M) is greater than or equal to the square of the scaling factor (A), the signal-to-noise ratio in quiescent mode is at least as high as that in normal operation. The repeating, scaling, and summing may all be performed in the frequency domain or in the time domain, as desired.

Abstract: A communications system including devices (10, 20) for transmitting and receiving wireless communications over licensed and unlicensed bands is disclosed. On the transmit side, a device (10) includes a plurality of message sources (8A, 8B, 8C) and a smart router (12) function executed by a processor (30) within the device. The smart router (12) function allocates each wireless transmission, or components of a multicomponent wireless transmission, over a licensed wireless link (LLTX) or an unlicensed wireless link (ULTX), by optimizing various factors. The allocation factors include the availability of the unlicensed and licensed channels within range of the transmitting device (10); quality of service parameters such as time delay limits, jitter limits, bandwidth requirements, and the like; cost tolerance and cost per minute factors; power consumption expectations; and a combination of these and other factors. Transmission of the wireless message over the selected wireless links is then carried out.

Abstract: A method for reducing the number of channels that are scanned during a handoff situation for a wireless endpoint station in a wireless local area network (WLAN), such as an IEEE 802.11 network, by tracking past user movements within the WLAN. A suitable sequence of channels to be scanned is generated so that reduce the number of handoffs are reduced and the average time during a handoff is reduced. To reduce handoffs and handoff latencies, the principle of locality (user movement patterns tend to be repetitive) is used. By tracking the past handoffs, future handoffs are predicted.