In one embodiment of the present invention, a memory storage system for storing information organized in sectors within a nonvolatile memory bank is disclosed. The memory bank is defined by sector storage locations spanning across one or more rows of a nonvolatile memory device, each the sector including a user data portion and an overhead portion. The sectors being organized into blocks with each sector identified by a host provided logical block address (LBA). Each block is identified by a modified LBA derived from the host-provided LBA and said virtual PBA, said host-provided LBA being received by the storage device from the host for identifying a sector of information to be accessed, the actual PBA developed by said storage device for identifying a free location within said memory bank wherein said accessed sector is to be stored. The storage system includes a memory controller coupled to the host; and a nonvolatile memory bank coupled to the memory controller via a memory bus, the memory bank being included in a non-volatile semiconductor memory unit, the memory bank has storage blocks each of which includes a first row-portion located in said memory unit, and a corresponding second row-portion located in each of the memory unit, each of the memory row-portions provides storage space for two of said sectors, wherein the speed of performing write operations is increased by writing sector information to the memory unit simultaneously.

Increasing the memory performance of flash memory devices by writing sectors simultaneously to multiple flash memory devices

A method and apparatus for allocating subcarriers in an orthogonal frequency division multiple access (OFDMA) system is described. In one embodiment, the method comprises allocating at least one diversity cluster of subcarriers to a first subscriber and allocating at least one coherence cluster to a second subscriber.

Ofdma with adaptive subcarrier-cluster configuration and selective loading

An antenna apparatus, which can increase capacity in a cellular communication system or Wireless Local Area Network (WLAN), such as an 802.11 network, operates in conjunction with a mobile subscriber unit or client station. At least one antenna element is active and located within multiple passive antenna elements. The passive antenna elements are coupled to selectable impedance components for phase control of re-radiated RF signals. Various techniques for determining the phase of each antenna element are supported to enable the antenna apparatus to direct an antenna beam pattern toward a base station or access point with maximum gain, and, consequently, maximum signal-to-noise ratio. By directionally receiving and transmitting signals, multipath fading is greatly reduced as well as intercell interference.

Adaptive antenna for use in wireless communication systems

Provided are a radio transmission device and a radio transmission method capable of improving downlink and uplink throughput even when performing dynamic symbol allocation. In the device and the method, BS and MS share a table correlating a basic TF as a combination of parameters such as TB size used for transmitting only user data, an allocation RB quantity, a modulation method, and an encoding ratio, with a derived TF having user data of different TB size by combining L1/L2 control information. Even when multiplexing L1/L2 control information, Index corresponding to the basic TF is reported from BS to MS.

Radio transmission device and radio transmission method

Systems and methods are described for determining position of a receiver The positioning system comprises a transmitter network including transmitters that broadcast positioning signals The positioning system comprises a remote receiver that acquires and tracks the positioning signals and/or satellite signals The satellite signals are signals of a satellite-based positioning system A first mode of the remote receiver uses terminal-based positioning in which the remote receiver computes a position using the positioning signals and/or the satellite signals The positioning system comprises a server coupled to the remote receiver A second operating mode of the remote receiver comprises network-based positioning in which the server computes a position of the remote receiver from the positioning signals and/or satellite signals, where the remote receiver receives and transfers to the server the positioning signals and/or satellite signals

Wide area positioning system

In satellite phased-array antennas, mechanical distortions, which may be due to vibrations caused when launching the satellite into the orbit or thermal variations in the orbit, result in significant degradation of electrical performance. In this paper, two on-board calibration methods are proposed for such mechanical distortions: One compensates for the element phase differences resulting from mechanical distortions, and the other is used to set the best-fit phase distribution obtained from the measured phases. The latter method is effective even at a low signal-to-noise ratio (SNR). The proposed methods have been validated by experiments, through which the theoretically predicted calibration accuracy of the methods has been successfully reproduced.

On-Board Calibration Methods for Mechanical Distortions of Satellite Phased Array Antennas

The authors present a novel method for the analytical determination of the amplitude distribution providing the low sidelobe pattern of conformal array antennas. The proposed projection method considers both the nonuniform element density and element patterns on the aperture. Numerical results are given as well as results of experimental verification for an X-band, half-spherical array with 60 rectangular microstrip antennas. >

A projection method providing low sidelobe pattern in conformal array antennas

PROBLEM TO BE SOLVED: To detect the position of a mobile unit with higher accuracy. SOLUTION: The subject mobile communication system is provided with at least one mobile unit 6 that measures reception signal power from plural adjacent base stations and plural base stations 1, 2, 3 each of which calculates round-trip propagation delay time by subtracting a processing time in a concerned base station and the mobile unit from a time difference between a reception start timing of a received signal received fastest and a transmission end timing to the mobile unit and estimates the distance from the mobile unit 6 based on the round-trip propagation delay time and a radio wave propagation speed, the position of the mobile unit 6 during communication can be detected based on the distance between the mobile unit and an adjacent base station estimated according to the reception signal power of the mobile unit 6 during communication and of the distance between the mobile unit and the communication base station estimated by the base station during communication with the mobile unit 6.

Mobile communication system, mobile unit and base station configuring the system and method for detecting position of the mobile unit in the system

PROBLEM TO BE SOLVED: To provide an antenna measuring device and a measuring method capable of measuring precisely excitation amplitudes and phases of each antenna element in consideration of amplitudes and phase errors of phase shifters and the amplitude and the phase error of a combined electric field in the operation state of all element antennas. SOLUTION: This device is equipped with an array antenna 5 including element antennas 41-4N and phase shifters 31-3N connected to the antennas respectively, a facing antenna 6 installed facing to the antenna, a transmitter 7 and a receiver 8 for radiating a signal from one side to the other side of the array antenna and the facing antenna and for receiving the radiated signal, a control device 1 for controlling the phase shifters based on the received output, an operation circuit 9 for measuring the amplitude and the phase change of the combined electric field of the array antenna from the received output when phase setting of each phase shifter is changed, and an operation circuit 10 for estimating the amplitudes and the phase errors of each phase shifter and the amplitude and the phase error of the combined electric field of the array antenna from the measurement result and for obtaining the relative amplitude and the phase of a radiated electric field relative to each element antenna.

Antenna measuring device and antenna measuring method

Digital beamforming (DBF) antennas are developing as advanced phased array antennas. The microwave signal received at each element antenna of the DBF array antenna is converted to a digital signal after downconversion. Beamforming is carried out in a digital processor, so both excitation amplitudes and phases can be controlled more precisely in the DBF than in the conventional phased array antenna. The DBF also has the advantage of adaptive array antenna signal processing. This allows the nulls of an antenna radiation pattern to be steered in the directions of interference signals. Adaptive array antennas are applied to the base station antennas of mobile communications. In this presentation, in TDMA and CDMA communication systems, the adaptive array antenna fit to each system is shown.

Isamu Chiba

Papers

On-Board Calibration Methods for Mechanical Distortions of Satellite Phased Array Antennas

A projection method providing low sidelobe pattern in conformal array antennas

Mobile communication system, mobile unit and base station configuring the system and method for detecting position of the mobile unit in the system

Antenna measuring device and antenna measuring method

Adaptive array antenna for mobile communication