Abstract:
In a receiver of a multi-leveled variable sideband communications system, a method is provided that comprises the steps of: dividing the receiver into a real portion and a complex portion; and providing a decision feedback equalizer (DFE) processing data substantially in the real portion.
Abstract:
A method used in a time domain equalizer is provided. A method comprising the steps of: providing a time domain equalizer comprising a feed forward equalizer and a feedback equalizer; and using a filter circuit or structured implementation to incorporate conjugate gradient iteration in order to calculate a set of coefficients of the time domain equalizer. Whereby matrix times vector operations is converted into filtering using the filter circuit.
Abstract:
A securing device includes a securing member defining a securing hole therein, and a fastener extending through the securing hole. The fastener includes a spring, and a bolt having a main portion, a bottom fixing portion, and a top head portion. The securing hole includes a large portion, a small portion, and a concave around the small portion. A diameter of the small portion is greater than the main portion and smaller than the fixing portion. A diameter of the large portion is greater than the fixing portion and smaller than the spring. The main portion extends through the small portion with the fixing portion tightly abutting the securing member. The spring is mounted around the main portion and received in the concave. The spring is compressed between the head portion and a step of the securing member in the concave.
Abstract:
This invention relates to a main-box-and-auxiliary-box-structural twin-countershaft twelve-speed transmission, with a main box and an auxiliary box mainly. Said main box has an input shaft (1), a main shaft (10) and two countershafts (14) arranged symmetrically at the two sides of the main shaft, there being provided corresponding gear drive between the main shaft and the countershafts, there being provided six gears positioned independently and three synchronizers (4) on the main shaft, shift forks (5) for the synchronizers are connected to a shift lever via shift fork shafts (16) and via an operation mechanism. The auxiliary box has an auxiliary-box main shaft (20) and an auxiliary-box countershaft (22), a gear (29) engaging with a gear (28), a gear (25) engaging with a shaft gear (30), between the gear (25) and the gear (29) being arranged a synchronizer (9), a shift fork (15) and a shift fork shaft (31), said synchronizer (9) being self-locked by means of back taper teeth, and said shift fork shaft (31) being self-locked by means of a self locking mechanism comprising a spring (18) and a steel ball (19).
Abstract:
In a TDS-OFDMA communications system, a frame structure comprising: a frame such that within a frame time, a transmitted signal comprising a preamble, a downlink sub-frame, and an uplink sub-frame; and interposed between OFDM symbols are guard intervals comprising known sequences being used for an estimation of a received power.
Abstract:
In an OFDM system having pseudo-noise (PN) sequences as guard intervals, a method for channel estimation and equalization is provided. The method comprising the steps of: providing a frequency equalization scheme; providing a time domain filter; and combining the frequency equalization with time-domain filter, thereby a time lag effect is taken into consideration for the channel estimation and equalization.
Abstract:
In an orthogonal frequency division multiplexing (OFDM) multiple-input multiple-output (MIMO) wireless communication system where both a transmitter and a receiver include a plurality of antennas, a method comprising the steps of: a receiver using at least one pseudo noise (PN) to associate desired information relating to a received symbol; and transforming the correlated information into frequency domain.
Abstract:
A disk drive includes a disk drive base, a disk, and a head stack assembly rotatably coupled to the base adjacent the disk surface of the disk. The disk drive includes an airflow channeling enclosure. The enclosure includes an airflow inlet disposed downstream of the head stack assembly and configured to receive the disk rotation induced airflow therethrough. The enclosure further includes an airflow channel extending along the disk surface from the airflow inlet. The enclosure further includes an outer wall extending along the disk surface from the airflow inlet and defining the airflow channel radially interior to the outer wall. The enclosure further includes an airflow outlet disposed upstream of the head stack assembly extending from the outer wall and the channel opposite the airflow inlet for modifying the disk rotation induced airflow passing from the channel.
Abstract:
A receiver adapted to receive both OFDM signals and single carrier signals is provided. The receiver possesses substantially commonly shared circuitry or function blocks, except an IFT (inverse Fourier transform) block adapted a receive frequency domain signals from a channel equalizer for converting the received frequency domain signal to a time domain signal, and a bypass for bypassing the IFT.
Abstract:
A method for constructing a simplified trellis diagram for BCH-encoded information is disclosed. BCH-encoded information is received, having a corresponding parity check matrix H. The parity check matrix H is expressed as an ordered sequence of columns of matrices. A sequence of sub-code words is provided, corresponding to one or more code words, each satisfying a given condition. A matrix Hcp, having columns that are generated as a selected permutation of the columns of the matrix H through a column-permutation-for-binary-matching process, is provided, and a sequence of sub-matrices and a corresponding sequence of permuted sub-code words is provided. A trellis diagram, representing an ordered sequence of code word transitions in the received information and symmetric about a central location, is provided for each code word c, connecting n+1 stages, numbered i=0, 1, . . . , n, in an ordered sequence.