Abstract: Media Access Control (MAC) layer transmit and receive buffering with multi-level prioritization. The receive buffering allocates receive buffers for receiving frame data from a PHY interface in priority order using both a static and dynamic buffer allocation, and delivers completed buffers queued in a multi-level priority queue to a host interface highest priority first. The transmit buffering delivers completed buffers queued in a multi-level priority queue to the PHY interface in priority order. When the multi-level priority queue contains a buffer that is higher priority than one being prepared for transmit, a priority-based interruption causes the transmit processing of the buffer to be suspended at its current state with the higher priority buffer taking its place. Upon completion of the higher priority buffer, the suspended buffer is resumed at its current state.

Abstract: A reduced inductance power distribution pattern for an integrated circuit (IC) package is disclosed. The IC package can include a die in which the electronic circuitry is formed, a ball grid array (BGA) substrate, and a plurality of conductive balls coupled to the BGA substrate. The IC package can further include a plurality of conductive trace rings routed in parallel, and a plurality of bond wires for coupling the die to the conductive balls via the conductive trace rings.

Abstract: A voltage buffer with current reuse is described. This voltage buffer can advantageously provide a relatively wide voltage differential using a relatively low current. In one embodiment, a slave branch can be used to minimize potential spikes/glitches in the voltage buffer.

Abstract: A method and corresponding system for communicating between stations in a network are presented. The method includes providing repeated beacon transmissions from a coordinator station for coordinating transmissions among a plurality of the stations; transmitting from a first station to a second station during a time slot assigned to the first station by at least one of the beacon transmissions; and transmitting from the first station information that grants permission to the second station to transmit during at least a portion of a time slot assigned to the first station.

Abstract: A method of designing stacked circuits for an integrated circuit is described. In this method, a plurality of devices that are stackable may be determined. Some of those devices, i.e. a subset of stackable devices, may be formed in a deep n-well, thereby allowing that subset of stackable devices to receive an increased supply voltage. The remainder of the stackable devices may be formed in a standard n-well, thereby allowing such devices to receive a standard supply voltage. In one embodiment, the standard supply voltage may be VDD and the increased supply voltage may be 2×VDD. This method may be advantageously used in both the design of stacked circuits for and the implementation of stacked circuits in an integrated circuit.

Abstract: A method for determining a position uses an access point array, a reference station, a location server and a client terminal. The reference station may include a GPS receiver to acquire and track GPS satellites. GPS data may be provided to the location server. The access point array may be configured to minimize interference and may be coupled by a network to the location server. The client terminal may include a GPS receiver. A frequency offset for the client terminal may be determined by examining a frequency offset of the reference station and relative offset frequencies of the access points. This frequency offset may advantageously increase the sensitivity of the client terminal to GPS signals. The client terminal may provide GPS data to the location server, which server may determine the position of the client terminal based on data from the client terminal and the reference station.

Abstract: A radio communication device is tested by forwarding relevant signal characteristic data derived at the physical (PHY) layer to the media access control (MAC) layer for processing, analysis and feedback to the radio circuit to improve performance. The relevant signal characteristics are forwarded to the MAC within (appended to) a data packet. Thus, the relevant signal characteristic is forwarded to the MAC along an existing data path (a path originally designed to transfer the receive frame only, but now transfers the combined receive frame with the attached radio characteristic). The radio characteristic may be used for testing and/or tuning the radio circuit. In one embodiment, the radio characteristic is a frequency domain representation of a received signal. The radio is tuned based on a channel estimate derived from comparison of frequency domain representations of transmitted and received signals.

Abstract: A system and method for closely synchronizing the transmission of real-time data streams is described. Synchronization data is transmitted by a cycle master for receipt by one or more cycle slaves. A cycle slave updates an internal state based on synchronization data received from the cycle master. This internal state may govern reproduction of received real-time data streams by the cycle slave. Such synchronization data may be inserted into transmitted media streams. The cycle slave internal state may be more accurately set by calculating timing differences between the cycle master and cycle slave and periodically adjusting that internal state between receipt of the synchronization data from the cycle master.

Abstract: An apparatus and method for providing electrostatic discharge protection of a transmit integrated circuit including an ESD protect block coupled to an integrated circuit pad in a package without bond wires, and an ESD clamp circuit coupled between the ESD protect block and ground. During transmission, one or more capacitors within the ESD protect block may charge up to various levels near the peak transmit voltage, which reverse biases one or more diodes in the ESD protect block, thereby buffering the transmit circuit from the capacitive load of the ESD clamp circuit. The ESD protect block may prevent the ESD clamp circuit from activating due to the high peak voltages output from the transmit circuit. An embodiment of the ESD protect block may apply particularly to transmit power amplifier circuits in which the output signal peaks at twice the supply voltage. In one embodiment applicable for lower voltage CMOS processes, the ESD protect block includes a diode and a capacitor.

Abstract: A method of generating a quadrature local oscillator (LO) frequencies is provided. In this method, a voltage-controlled oscillator (VCO) frequency can be mixed with a divided version of the VCO frequency to generate mixed signals. A lower sideband of the mixed signals can be selected for the quadrature LO frequencies to minimize the occurrence of spurs. Notably, the divided version is 1/N of the VCO frequency and the VCO frequency is a radio frequency (RF) channel frequency times a ratio N/(N?1).

Abstract: An amplifier with linearization feedback includes an amplification stage that receives a feedback control signal from an envelope detection feedback network. The envelope detection feedback network controls the gain of the amplification stage based on an envelope of an input signal of the amplification stage, an envelope of an attenuated version of an amplified output signal of the amplification stage, and an offset adjustment signal generated by an offset calibration block. The envelope detection feedback network can include single stage or multiple stage envelope detectors. The amplification stage can include multiple, serially connected amplifiers. The gain of at least one amplifier in the amplification stage may be controlled by the feedback control signal. Additionally, the gain of some of the amplifiers in the amplification stage may be controlled digitally by gain adjustment signals based on comparing the feedback control signal to one or more reference signals.

Abstract: An RF coupling circuit including a transformer and a parallel AC-coupling capacitor can advantageously ameliorate substantial attenuation of a signal, prevent destabilization of any feedback loop, and simplify the circuit design process. The AC-coupling capacitor can act as an “averager”, i.e. both the input and output sides of coupling circuit represent capacitances equal to the average of the input and the output capacitances. Thus, the inductors for tuning them out can become equal, thereby allowing a symmetric (or near symmetric) transformer to be used in the RF coupling circuit. When tuned properly, the transformer plus AC-coupling capacitor can also advantageously provide better in-band gain as well as frequency selectivity than other conventional coupling circuits.

Abstract: A voltage buffer with current reuse is described. This voltage buffer can advantageously provide a relatively wide voltage differential using a relatively low current. In one embodiment, a slave branch can be used to minimize potential spikes/glitches in the voltage buffer.

Abstract: A system and method are described for repeatedly and efficiently performing a wireless communication channel survey to determine whether comparable communications devices exist, which frequencies are in use, and the identities of the comparable communications devices. A beacon data table stores received beacon data which is used to predict beacon arrival times, thereby allowing a receiver to be tuned away from an active data communications channel for a shorter dwell time than a beacon period. A further efficiency can be gained if beacon generators cooperatively stagger their beacon times according to one or more measurable characteristics of the beacon generator, e.g. the operating channel number and the SSID.

Abstract: A modified approach to detecting the start frame delimiter (SFD) is disclosed. A receiving system scans a decoded but not yet de-scrambled received signal for a scrambled version of the SFD associated with the preamble format being used. Using this approach, it is not necessary to use any bits intended for use in synchronization to initialize a de-scrambler so as to be able to de-scramble the SFD portion of the preamble for detection. The bits that otherwise would have been dedicated to initializing the de-scrambler may then be used for synchronization, as intended. Detecting fewer than all bits comprising a start frame delimiter is described. Bits not used for SFD detection may be used for other purposes, such as synchronization.

Abstract: An accurate total error rate performance can be measured using a computed error vector magnitude (EVM) per stream. Using this EVM, the receiver or the transmitter can advantageously generate an optimized modulation and coding scheme (MCS) that corresponds to a specific number of streams, modulation and coding rate for the transmitter. For example, the receiver can compute an SNR from the EVM and then use an SNR vs. MCS table to determine the optimized MCS. In contrast, the transmitter can receive an EVM-to-RSSI mapping and an EVM-to-MCS mapping from the receiver. These mappings and an EVM can facilitate selecting the optimized MCS.

Abstract: Methods and systems are operable to aggregate data. A plurality of data units can be received. The data units can be combined based upon a class associated with the data and a next hop associated with the data. A link can be provided for the combined data units based on service quality requirements for the traffic class associated with the class.

Abstract: Background scanning can include using a power save mode to momentarily suspend transmission between a current access point and a client. Information regarding other access points can then be collected. The client can return to the current access point before communication between the client and the current access point is disrupted.

Abstract: A method and corresponding system for communicating between stations in a network are presented. The method includes providing repeated beacon transmissions from a coordinator station for coordinating transmissions among a plurality of the stations; transmitting from a first station to a second station during a time slot assigned to the first station by at least one of the beacon transmissions; and transmitting from the first station information that grants permission to the second station to transmit during at least a portion of a time slot assigned to the first station.

Abstract: Techniques are disclosed for detecting a packet. One technique includes sampling a received signal to produce a sequence of samples wherein the sequence of samples includes a plurality of subsequences of samples; cross correlating the subsequences of samples with a known form of the subsequence to produce cross correlations; self correlating the cross correlations to produce a plurality of self correlations; summing the self correlations; and processing the sum of the self correlations.