Abstract: Two novel subchannelization methods are disclosed, for use in a 802.16m system. A downlink subchannelization method supports both localized and distributed sub-carriers, different modulation modes, and supports a variety of different fractional frequency reuse (FFR) group allocations.

Abstract: A novel pilot method employs a cluster having a particular arrangement of pilot sub-carriers to optimize transmissions under 802.16 m, or WiMAX-II. The optimally configured cluster features equal pilot density per OFDM symbol, two or more pilot sub-carriers per cluster, and interlaced pilot sub-carriers, which enables the base stations to successfully boost the pilot sub-carriers, for optimum performance.

Abstract: An adaptive mode transmitter enables either OFDMA or SC-FDMA modulation schemes to be used during transmission of a wireless signal, such as during mobile phone use. The modulation scheme is selected automatically, and is based on characteristics of the transmitting entity, such as bandwidth allocation, selected modulation order, and transmit power.

Abstract: An extended range preamble is disclosed, for transmission between extended range 802.11n devices. The extended range preamble consists of a high-throughput signal field, in which a modulation coding scheme rate and payload length are specified by the transmitting device. The extended range preamble also includes an expanded preamble, which is adjacent to the high-throughput signal field, and is not understood by non-extended range devices. The modulation coding scheme rate is specified as either one of the rates supported in non-extended range 802.11 devices or as a reserved modulation coding scheme not understood by the non-extended range devices. In either circumstance, the non-extended range device respects the preamble, and thus does not itself attempt a transmission during processing of the preamble.

Abstract: A system and method for determining whether sampled spectrum data comes from a cordless phone is disclosed. The system includes a device to detect the sampled spectrum data and an algorithm to analyze the sampled spectrum data. The algorithm separates the narrowband components from the wideband components of the sampled spectrum data, then classifies the sampled spectrum data based on the bandwidth, frame length, and inter-frame time, as either being an analog or digital FM phone, a DSSS phone, a WDCT phone, or a non-cordless phone, such as a Bluetooth device. The algorithm may be used for interference mitigation.

Abstract: A flexible start time (FST) scheduling algorithm operable at a base station is disclosed, to allocate resource in the time domain based on coexistence period bitmap (CBP) feedback gathered from multi-radio user terminals. The algorithm analyzes traffic load distribution in the wireless neighborhood and determines an optimum starting time of the CBP operation for the current user.

Abstract: A novel out-phasing-array transmitter system and method are disclosed. The method is based on decomposing the input signal into an array of signals to drive a general, multiple paths out-phasing-array transmitter. This decomposition is less sensitive to the phase difference between the multiple paths, and extends the dynamic range of the out-phasing-array transmitter system. The wide dynamic range and the multiple transmission paths increase the maximum achievable output power, in accordance with the WiMAX specifications.

Abstract: A unified open loop single-user/multiple-user multiple-input-multiple-output (MIMO) system and method are disclosed. The system and method operate without use of channel state information feedback. Instead, the method utilizes channel quality indicator feedback to schedule users to spatial resource blocks. Both symmetric multi-user MIMO schemes (like 2×2 and 4×4) and asymmetric multi-user MIMO schemes are considered. CQI feedback and reduction proposals are also introduced. The method may be used in a proposed network topology.

Abstract: A phase noise minimization circuit is disclosed, to be used in a voltage-controlled oscillator (VCO) circuit embedded in a feedback system. The phase noise minimization circuit includes a noise power meter to analyze the control voltage fed into the VCO by the feedback system and determine its voltage noise power. Since the VCO is controlled by the feedback system, the control voltage noise power is also an indication of the VCO phase noise power for frequencies offset within the bandwidth of the feedback system. The VCO has several parameters that can be adjusted to affect its phase noise. A minimization algorithm generates the optimum set of parameters that minimize the control voltage noise power (and thus the VCO phase noise power), and sends them to the oscillator. The phase noise minimization circuit may be used in a variety of applications, particularly in phase-locked loop and frequency-locked loop VCOs.

Abstract: A collocated radio coexistence method is disclosed. The method operates in the frequency domain to protect WiMAX downlink traffic from narrow band interference (e.g. harmonics) caused by other collocated radios, such as GSM 800 MHz, operating simultaneously with an 802.16-capable (WiMAX) radio in a multiple radio coexistence platform (MRP).

Abstract: A transmit and receive machine (TRM) is part of a medium access controller (MAC), in support of the 802.11 wireless standard. The TRM is a control machine that changes the MAC within which it resides from a purely software-based MAC into a software and hardware management system. Timing-critical tasks that were once performed by the embedded processor of the MAC are performed by the TRM. This change enables the MAC to operate at a high speed while the TRM maintains high accuracy of transmit and receive timing operations.

Abstract: An adaptive receiver algorithm is disclosed, for use in multiple-input-multiple-output orthogonal frequency division multiplexing systems. The adaptive receiver algorithm selectively chooses either the maximum ratio combining technique or the minimum mean square error technique, for optimum receiver performance, depending on the characteristics of the wireless environment.

Abstract: A web-based system is disclosed for managing radiology services for one or more medical facilities. The system, comprising both hardware and software components, provides mechanisms by which radiographic images and demographic information about a patient are transmitted to a central location and efficiently combined, allowing a designated radiologist to efficiently interpret the radiographic images and produce a preliminary report. The central location includes web-based, secure access by which multiple entities may interpret and update the preliminary report. Although the system is designed with after-hours radiology services in mind, the system may be employed in radiology departments during regular weekday operation.

Abstract: A mobile channel estimation algorithm is disclosed, for use in a DVB-H coded OFDM demodulator. The mobile channel estimation algorithm estimates the mobile channel transfer function, overcoming many of the delay spread limitations without using time filtering and without having to collect many OFDM symbols. Once the channel estimate has been found for each symbol, equalization and inter-carrier-interference cancellation may be carried out relatively easily using known methods. The mobile channel estimation algorithm may be used in DVB-H as well as in other areas of OFDM.

Abstract: A weighted tone reservation (WTR) method and system are disclosed, for PAPR reduction. The WTR method solves the peak re-growth problem with minimum overhead. By avoiding the drawbacks of conventional tone reservation approaches, systems employing the WTR method may experience a significant PAPR reduction. The WTR method may be applied to next generation OFDMA-based wireless broadband technologies to increase system throughput and cell coverage.

Abstract: An energy-efficient framework for active transmission in OFDMA-based long-range wireless networks is disclosed. This frame-work is based on using energy-aware metrics for resource allocation and link adaptation. By casting the optimal energy-efficient resource allocation problem as utility-based optimization problem, low-complexity utility-based resource allocation schemes developed here can be applied to reduce the complexity of resource allocation decisions.

Abstract: Methods for modifying a central frequency of a channel following a change in channel width between wireless devices are disclosed. The station desiring a channel width change notifies the AP and enters a constructive power management mode, which keeps the AP from sending frames to the station. This enables the station to move the central frequency without concern of data loss, then restores itself to a full-power state. Or, the station communicates the desire to switch channel modes after receiving a beacon frame from the AP, then switches the central frequency of the channel during a subsequent beacon, or during some predetermined time period prior to the subsequent beacon. While the central frequency is being changed, the station does not miss a frame intended to be communicated to the station.

Abstract: A novel encoding scheme is disclosed, enabling the physical layer to identify packet boundaries by looking at a few selected bits while improving the error detection capability and maintaining low overhead for low power states. By eliminating the overhead of 8b/10b encoding for the physical layer, the encoding scheme achieves better error detection ability than current 8b/10b encoding. Further, the novel encoding scheme provides additional error detection capability, a low overhead mechanism to exit low power states, and a mechanism to handle problematic packets.

Abstract: A simultaneous satisfiability algorithm, or SSAT, allows simultaneous checks to be made efficiently for a number of literals, x1, . . . ,xn whether x1 is true under any satisfying assignments of a formula (written in conjunctive normal form) built from the variables of these literals and other variables (or, equivalently whether x1 is a logical consequence of the formula). Thus, several related satisfiability checks are performed simultaneously in SSAT. Temporal induction algorithms allow the verification of the sequential behavior of finite state machines, e.g., hardware. Temporal induction algorithms may employ a SSAT solver to perform simultaneous model checking of several invariant (or safety) properties efficiently. These SSAT-based temporal induction algorithms are double-incremental, such that all learned clauses in the SSAT solver are re-used both across verified properties as well as across time frames.

Abstract: A front side bus swizzle mechanism modifies the front side (address and data) bus on a chip so that, when the chip is positioned on one side of a printed circuit board, connection to a second chip located on the opposite side of the printed circuit board is simplified. The simplified connection may result in less complexity and minimize the consumption of additional printed circuit board real estate.