Abstract: Methods and apparatus are provided for per-antenna training in a multiple antenna communication system having a plurality of transmit antenna branches. A long training sequence is transmitted on each of the transmit antenna branches such that only one of the transmit antenna branches is active at a given time. The active transmit antenna branch is configured in a transmit mode during the given time and one or more of the inactive transmit antenna branches are configured in a receive mode during the given time. The transmit and receive modes are configured, for example, by applying a control signal to one or more switches.

Abstract: A multicast group list (i.e., destination node address list) for a network device is circularly linked such that the list can be entered at any point and traversed back to the entry point. The list traversal is then terminated as the entire list has been processed. The data packet received at the network device for transmission to the multicast group can indicate the entry point, although there are other techniques for determining the entry point. The destination node address for the entry point is skipped, that is the multicast data packet is not transmitted to the entry point destination address.

Abstract: A laser assembly comprises a substrate, one or more standoffs and a semiconductor laser. The substrate has a first doped region and a second doped region. The second doped region is proximate to an upper surface of the substrate and forms a pn junction with the first doped region. The semiconductor laser is operative to emit light from an upper surface and a lower surface. Moreover, the semiconductor laser is attached to the upper surface of the substrate with the one or more standoffs such that the light emitted from the lower surface of the semiconductor laser impinges on the second doped region.

Abstract: A method of using an intercom on a cordless telephone during an active call. The active call is put on hold while the intercom is in use. Once the call is re-activated, the intercom is shut off. This system may be designed for a cordless telephone with one handset or a plurality of handsets.

Abstract: Methods and apparatus are provided for detecting and decoding adaptive equalization training frames (having a frame marker comprised of a string of binary ones and binary zeroes). Training frames are detected by shifting the received data; inserting at least one binary value at one end of the shifted received data to generate a modified version of the received data; applying a logic function to the received data and the modified version of the received data that identifies when corresponding bit positions have different values; and detecting the frame marker when an output of the logic function has a first binary value in an approximate middle of a string of a second binary value. The training frames are decoded using a distance between the approximate center of the frame marker and a predefined binary value in an output of the logic function.

Abstract: A delay circuit having reduced duty cycle distortion is provided. The delay circuit includes a plurality of delay elements connected together in a series configuration. Each of the delay elements has a prescribed delay associated therewith. The delay circuit further includes a controller connected to respective outputs of the delay elements. The controller is configured such that signal paths between the respective outputs of the delay elements and an output of the controller have delays that are substantially the same relative to one another. Each of the signal paths has a tri-statable switching element associated therewith.

Abstract: In one embodiment of the present invention, the performance of an electronic circuit having a clock path between a clock source cell and a clock leaf cell is characterized over a simulation duration, where the clock path has one or more intermediate cells. Variations in the effective power supply voltage level of at least one intermediate cell over the simulation duration are determined using a system-level power-grid simulation tool. Static timing analysis (STA) software is used to determine cell delays for at least one of the intermediate cells for different clock-signal transitions at different times during the simulation duration. The cell delays are then used to generate one or more metrics characterizing the performance of the electronic circuit, such as maximum and minimum pulse widths, maximum cycle-to-cycle jitter, and maximum periodic jitter.

Abstract: The invention relates to a detection method using a receiver of a digital communication system for the detection of a symbol from a received signal, which signal is transmitted by a transmitter of the digital communication system, wherein the symbol is a selected symbol out of a predetermined set of symbols and wherein each symbol of the predetermined set comprises a sequence of chips wherein each of the chips is PSK-modulated according to a selected modulation code.

Abstract: An integrated circuit die includes a substrate having an upper surface, at least one active device formed in a first area of the upper surface of the substrate, and a plurality of layers formed on the upper surface of the substrate above the at least one active device. A first stacked heat conducting structure is provided, spanning from a point proximate the first area of the upper surface of the substrate through the plurality of layers. A lateral heat conducting structure is formed above the uppermost layer of the plurality of layers and in thermal contact with the first stacked heat conducting structure. The invention advantageously facilitates the dissipation of heat from the integrated circuit die, particularly from high-power sources or other localized hot spots.

Abstract: In one embodiment, a method for processing a series of MAC-hs protocol data units (PDUs) in an HSDPA-compatible (high-speed downlink packet access) receiver in a 3G wireless communication network, the method including: (a) receiving a MAC-hs PDU having: (i) a queue identification (QID), (ii) a transmission sequence number (TSN), and (iii) one or more MAC-d PDUs, (b) then disassembling the MAC-hs PDU (c) then distributing the one or more MAC-d PDU to a reordering queue indicated by the QID, and (d) then performing reordering processing for the corresponding reordering queue based on the TSN. Steps (a) and (b) are performed in a physical layer of the receiver. Steps (c) and (d) are performed in a data-link layer of the receiver.

Abstract: A cache memory architecture, a method of operating a cache memory and a memory controller. In one embodiment, the cache memory architecture includes: (1) a segment memory configured to contain at least one most significant bit (MSB) of a main memory address, the at least one MSB being common to addresses in a particular main memory logical segment that includes the main memory address, (2) a tag memory configured to contain tags that include other bits of the main memory address and (3) combinatorial logic associated with the segment memory and the tag memory and configured to indicate a cache hit only when both the at least one most significant bit and the other bits match a requested main memory address.

Abstract: A method and device for providing a communication session with a plurality of users. In one embodiment, the method includes: (1) transmitting an initiation message from the first terminal to the second terminal, the initiation message including a first address assigned to the first terminal, (2) dividing a display of the first terminal to simultaneously display text to be transmitted from the first terminal and text received from the second terminal, the dividing based on if there is text to be transmitted by the first terminal, (3) receiving the initiation message at the second terminal, (4) transmitting a first reply to the initiation message from the second terminal to the first terminal and (5) receiving the first reply at the first terminal.

Abstract: In one embodiment, a receiver comprises an automatic gain controller (AGC), an equalizer, a controller, and a register interface. The AGC makes gain adjustments to compensate for changes in the average amplitude of a received signal. The equalizer has a coefficient updater that calculates coefficients and a finite impulse response (FIR) filter that applies the coefficients to the received signal to generate an equalized signal. During gain adjustments by the AGC, the register interface provides a weight freeze signal to the coefficient updater, which subsequently freezes the updating of the coefficients for a freeze duration period. Then, register interface provides a scaling factor, generated by the controller based on the size of the gain adjustment, to the coefficient updater. At the end of the freeze period, coefficient updater applies the scaling factor to the coefficients and unfreezes the coefficient updating.

Abstract: An MOS device includes a semiconductor layer of a first conductivity type and first and second source/drain regions of a second conductivity type formed in the semiconductor layer proximate an upper surface of the semiconductor layer. The first and second source/drain regions are spaced apart relative to one another. A gate is formed above and electrically isolated from the semiconductor layer, at least partially between the first and second source/drain regions. At least a given one of the first and second source/drain regions is configured having an effective width that is substantially greater than a width of a junction between the semiconductor layer and the given source/drain region.

Abstract: A wireless telecommunication device conducts base station pages at large intervals, such as 30 seconds, rather than the more conventional 0.5 to 4 seconds. The network processes calls placed to that telecommunication device in accordance with an SMS (Short Messaging Service) type protocol rather than a conventional voice call protocol. Particularly, the network sends an SMS to the telephone indicating that a third party is calling (hereinafter termed a “pre-call SMS”). The pre-call SMS indicates the telephone number of the third party. The user of the telephone may call the third party back. In accordance with this protocol, the need to page at very short intervals so as to permit a telephone call to be established in “real-time” is eliminated. Therefore, the paging interval can be increased substantially, thereby substantially prolonging battery charge lifetime of the telephone.

Abstract: Methods and apparatus are provided for direct synthesis of RF signals using a delta-sigma modulator. An RF signal is synthesized from an input signal by quantizing the input signal using a quantizer, such as a one bit quantizer; determining a quantization error associated with the quantizer; generating an error prediction value using an error predictive filter, wherein the error predictive filter comprises one or more filter zeroes on a unit circle for one or more desired frequencies of f1, f2, . . . fn and one or more filter poles having a magnitude inside the unit circle and a frequency substantially equal to the one or more desired frequencies of f1, f2, . . . fn; and subtracting the error prediction value from the input signal. The filter poles have a magnitude that reduces a boost provided out-of-band.

Abstract: A method and apparatus are disclosed for performing joint equalization and decoding of multidimensional codes transmitted over multiple symbol durations. An RSSE scheme is disclosed that cancels the intrasymbol interference caused by other symbol components within the same multidimensional code symbol. The disclosed RSSE technique for multidimensional codes applies where the number of trellis code dimensions exceeds the number of channels. The disclosed RSSE decoder computes the intersymbol interference caused by previously decoded multidimensional code symbols and subtracts the intersymbol interference from the received signal. In addition, a branch metrics unit compensates for the intrasymbol interference caused by other symbol components within the same multidimensional code symbol.

Abstract: Described embodiments include a level shifter that provides a voltage level shift to applied signals, the amount of voltage shift being accurately controlled and independent of PVT. The level shifter has first transistor configured as a voltage follower with the gate coupled to an input terminal of the shifter and the source coupled to a node, a diode-connected transistor coupled between the node and an output terminal of the circuit, a first controlled current source coupled to the node, and a second controlled current source coupled to the output terminal. A controller receives a bandgap-stabilized voltage, squares the stabilized voltage to produce a control signal that controls the first and second controlled current sources. The voltage shift is proportional to a digitally-controlled scale factor (K) times the stabilized voltage. The ratio of the current from the first current source to the second current source is (K+1)/K.

Abstract: Methods and apparatus are provided for communicating data in a multiple antenna communication system having N transmit antennas. According to one aspect of the invention, a header format includes a legacy preamble having at least one legacy long training field and an extended portion having at least N additional long training fields on each of the N transmit antennas. The N additional long training fields may be tone interleaved across the N transmit antennas and are used for MIMO channel estimation. The extended portion may include a short training field for power estimation. The short training field may be tone interleaved across the N transmit antennas and have an extended duration to support beam steering.

Abstract: A method for controlling a transmission rate of at least one transceiver, the transceiver including a transmitter and a receiver, includes: determining a signal quality characteristic corresponding to a signal received at the receiver by measuring a difference between one or more reference constellation points and one or more received constellation points, and modifying a transmission rate of the transmitter over a wireless communication channel as a function of the signal quality characteristic.