Abstract: In one embodiment of the invention, a receiver has two mux circuits, two receiver circuits, and a mixer. The muxes select first and second input signals for the receiver circuits. A p-type transistor in a transmission gate in each mux is connected (i) at its channel nodes between a pad and the mux output and (ii) to receive a control signal at its gate node. Control circuitry for the p-type transistor implements a threshold reduction filter that ensures that a maximum voltage level at the mux output is at least a threshold below the mux's power supply voltage. Based on first and second input signals, the first receiver circuit generates first and second intermediate signals, and the second receiver circuit generates third and fourth intermediate signals. The mixer circuit combines the intermediate signals to generate first and second output signals, wherein the first and second receiver circuits effectively operate over different ranges of common-mode voltages.

Abstract: The present invention enhances the dynamic frequency selection 9DFS) algorithms used in Wireless LANs by adding a channel swapping mechanism. The aim of the traditional DFS algorithm is to dynamically select channels in a wireless LAN in such a way that the best performance is achieved. However, not always the optimal channel selection is achieved. This invention describes an addition to the DFS algorithm in such a way that two APs can decide to swap channels instead of one AP switching to another channel. To avoid the problem of sub-optimal channel selection, a requesting AP sends Swap Requests to other APs in order to sense the willingness of other APs to swap channels with the requesting AP.

Abstract: In one embodiment of the invention, an integrated circuit, such as an FPGA, has one or more programmable termination schemes, each having a plurality of resistive termination legs connected in parallel, and a calibration circuit designed to control each termination scheme for process, voltage, and temperature (PVT) variations. The sense element in the calibration circuit and each resistive leg in each termination scheme has a transistor-based transmission gate connected in series with a non-silicided poly (NSP) resistor. The negative temperature coefficient of resistivity of each NSP resistor offsets the positive temperature coefficient of resistivity of the corresponding transmission gate to provide a temperature-independent sense element and temperature-independent termination legs.

Abstract: A processor capable of independently adding a specified level of noise to each different frequency-based channel signal of a composite signal, where the specified levels of noise for at least two channel signals are different. In one embodiment, the processor operates in the digital domain after the composite signal can been channelized using a single set of time-multiplexed circuitry for all channel signals.

Abstract: In one embodiment, a network system has a plurality of access points, wherein each access point can be used for wireless communication with at least one station, wherein each access point can (1) receive a probe signal with either a first or second channel frequency and (2) generate and transmit, in response to the probe signal, a response signal with the first or second channel frequency. At least one access point selects at least one channel frequency for the wireless communication with the at least one station on the basis of at least one response signal received with the first channel frequency as transmitted by any of the other access points and/or at least one response signal received with the second channel frequency as transmitted by any of the other access points.

Abstract: In one embodiment, a (negative-voltage) charge pump with one or more stages that receives a (high) input voltage and generates a higher-magnitude (negative) output voltage. Each stage has two capacitors for storing charges and two branches that alternate to transmit a higher-magnitude output voltage at every clock half cycle. Each branch has a PMOS transistor and a NMOS transistor. To reduce the effects of back body from the substrate, two transistors are constructed with three wells and two with four wells, where the number of wells per device is dependent upon the substrate type used.

Abstract: A medium-reservation mechanism improves transmission efficiency in a multiple-channel network that includes stations with limited-selectivity receivers. The mechanism employs a medium-request signal that conveys channel information. In this network, stations check the channel information in the medium-request signal to decide whether or not to comply with the medium-request signal. If the channel information identifies the channel that is close to the channel that the station is presently operating on, the station then complies with the medium-request signal. If the channel information identifies a channel other than the channel that the station is presently operating on, the station ignores the medium-request signal.

Abstract: In a multiple-input, multiple-output (MIMO) system, a receiver is implemented with at least one additional receive path beyond the number of transmit antennas used to transmit the signals (e.g., wireless OFDM signals) received at the receiver. In one embodiment, the additional receive path is used to reduced co-channel interference (CCI) in the recovered OFDM signals. In particular, each receive path applies recursive filtering to generate separate subcarrier signals. A processor converts the separate subcarrier signals from the different receive paths into a first set of subcarrier signals corresponding to each transmitted OFDM signal, where each first set of subcarrier signals has desired signal and possibly CCI. The processor also generates a second set of subcarrier signals corresponding to the CCI. The processor subtracts portions of the second set of subcarrier signals from each first set of subcarrier signals to generate recovered OFDM signals having reduced CCI.

Abstract: Methods for fabricating robust films across a patterned underlying layer's edges or steps are disclosed. The novel methods diminish the negative effects of electrode steps or edges on the integrity of a membrane. Thus, the methods are particularly applicable to membrane release technology. The height of the step or edge is eliminated or reduced to increase the mechanical integrity of the film.

Abstract: An electronic module has a non-conducting substrate having at least one opening and a die/carrier assembly mounted within the opening in the substrate. The assembly has a conducting carrier and one or more integrated circuit (IC) dies mounted to the carrier. The invention may be implemented as an electronic system comprising a circuit board (CB) and at least one such electronic module mounted to the CB.

Abstract: A structured interleaving/de-interleaving scheme enables efficient implementation of encoding/decoding based on two-dimensional product codes (2D PC). In one embodiment, an encoder has an integrated architecture that performs structured interleaving and PC coding in an integrated manner in which locations in the interleaved data stream are related to row and column indices for the 2D PC coding based on closed-form expressions. A corresponding decoder implements two-stage low-density parity-check (LDPC) decoding based on the same relationships between locations in the interleaved data stream and row and column indices for the LDPC decoding.

Abstract: A logic circuit is disclosed that is tolerant of logic signals with voltages different from the voltage of the logic circuit power supply. In one embodiment, the logic circuit has an inverting amplifier therein, the amplifier having at least one input and an output and is powered by the power supply. A first transistor, in responsive to the output of the amplifier, biases the input of the amplifier to assure substantially no static current flows through the amplifier when a logic-low is present on the amplifier output. A second transistor couples at least one logic input of the logic circuit to the input of the amplifier. In one embodiment, the second transistor impedes static current flow from the first transistor, through the second transistor, to the logic input. Various other embodiments of the logic circuit include a latch/flip-flop, multiplexer, and a complex logic gate.

Abstract: A packet network employs routers that determine network routing based on quality of service (QoS) provisioning parameters and network topology information. QoS provisioning parameters are provided to each router from a network management database, and the network topology information is determined from a link state database of the router. The link state database may include network topology information collected by the router in accordance with the open shortest path protocol (OSPF). A network link, router, or other node failure initiates a new path-selection process. First, a temporary set of provisioning entries may be determined with a shortest path first (SPF) routing method. Then, the network packet flows may be classified into packet flows, real-time and non-real-time, and then as packet flows that require reserved bandwidth or that may be multiplexed.

Abstract: A packet network of interconnected nodes employs a constraint-based routing method to determine a path through the network for a requested label-switched path (LSP). Each of the nodes includes one or more routers that forward packets based on a forwarding table constructed from paths determined in accordance with the constraint-based routing method. The constraint-based method determines the path of the requested LSP based on the effect that routing those packets of the requested LSP may have on current and/or future demands on the capacity of network nodes for currently provisioned LSPs. Such constraint-based routing method may not necessarily route packets of a requested LSP along the shortest path, or minimum number of hops, through the network. Given the packet network and LSP request, a linear programming system is defined by a set of linear programming equations.

Abstract: A receiver scans through two different search windows to detect a received signal: a first search window and a second search window. The timing of the second search window is adjusted after every processing cycle to follow the detected signal, while the timing of the first search window remains fixed. If the timing of the detected signal remains relatively constant for a sufficient period of time, then the timing of both the first search window and the second search window are adjusted based on the timing of the most recently detected signal. In this way, the receiver can continue to detect the received signal, even when the timing of the received signal varies greatly over time, without necessarily changing the first search window.

Abstract: Error control coding is applied to data streams transmitted through transmission equipment such as a telecommunications switch having a distributed synchronous switch fabric. Each k-symbol dataword is encoded to generate an n-symbol codeword that is then sliced for transmission through the transmission equipment. After routing, error-correction decoding is applied to the resulting routed n-symbol codeword to detect and correct one or more errors in the codeword to generate a k-symbol routed dataword that is identical to the original incoming dataword. Depending on the coding scheme, different types and numbers of errors can be corrected in each codeword. For example, for Reed-Solomon [12, 8, 5] coding with Galois field (24), corrections can be made for up to four erasures with no random errors, up to two erasures and one; random error, or up to two random errors with no erasures.

Abstract: A packet network employs flow control providing assigned rates to sessions in accordance with a general max-min (GMM) rate allocation. The GMM rate allocation accounts for the minimum cell rate and peak cell rate requirements for each session. For one case, a centralized flow control algorithm is employed that sorts sessions based on increasing minimum cell rate. The centralized flow control algorithm employs an iterative process of increasing the rate of the smallest rate session and adding sessions to the process when the smallest rate session equals the next higher rate session. The rates are increased until the rate either reaches the peak cell rate of the session or the link saturates. For a second case, a distributed flow control algorithm is employed with a distributed protocol within the network to allocate capacity of network links to sessions. For the distributed flow control algorithm, an iterative process of rate allocation uses a modified version of the Consistent Marking method.

Abstract: A back haul architecture enables efficient primary transfer (i.e., transfer of the designation of primary base station from one base station to another). A frame selection/distribution (FSD) function queues packets of forward-link data—to which sequence numbers have been assigned—for packet-mode transmission over the back haul only to one base station—the current primary base station—where the packets are again queued for over-the-air transmission to the mobile unit. If and when it becomes appropriate to transfer the designation of primary base station to another base station, there may still be packets of data queued at the old primary base station awaiting transmission to the mobile unit. The old primary base station sends a message to the new primary base station indicating a particular sequence number that identifies the remaining packets of forward-link data queued at the old primary base station.

Abstract: A mobile communications system employs extended channel assignment messaging during the call setup portion of a mobile call. As part of the call setup process, a mobile station sends an access request message to a primary base station that includes a list of alternate base stations. As call setup continues, the mobile station employs diversity reception in monitoring the paging channel of three base stations, each selected as a function of the strength of the signal-to-noise ratios of their respective pilot tones.

Abstract: A technique for bridging the gap between an initial call and a return call by using network capabilities to capture the caller's information and by providing efficacious means for reaching the caller at a later time. The subscribed user, i.e., the called party, is provided with an opportunity to access a self-generating return call list which stores the names and the telephone numbers of the callers who could not speak to the subscribed user e.g., the subscribed user was not available to answer within a predetermined number of rings or was busy with another call. In addition, the system may be configured to create entries in the return call list for all incoming calls to the subscribed user, irrespective of whether the incoming calls were answered or not. The subscribed user may at any time access the return call list, either from his own telephone or some other DTMF telephone set.