Abstract:
Estimating the speed of movement of a mobile terminal of a wireless communication system communicating with a base station includes calculating a normalized auto-covariance of the instantaneous power of the signal received by the mobile terminal or by the base station.
Abstract:
The transmission power of a cellular mobile telephone is adjusted as a function of received power information. The celluar mobile telephone is equipped with a variable-gain amplifier that covers the transmission power range, and the gain and supply voltage of the amplifier are tuned as a function of the received power information.
Abstract:
A first estimate is made of the impulse response of the channel considered as a whole, then this first estimate is corrected independently of the information transmitted for obtaining a corrected final estimate of the impulse response of the channel. This is done by taking account of the fact that the impulse response of the sender and the impulse response of the receiver are known.
Abstract:
A method and apparatus for performing head switch operations in a magnetic disk system with a magnetic disk device that is segmented into a plurality of cylinders. The cylinders are grouped into an inner zone, a middle zone, and an outer zone. The inner zone is near the innermost area of the magnetic disk device. The outer zone is near the outermost area of the magnetic disk device. The middle zone is in between the inner zone and the outer zone. The head switch is performed from a current head at a current cylinder to a target head at a target cylinder. Prior to the head switch, the system determines if the current cylinder is in either the inner zone or the outer zone. If the current cylinder is in either the inner zone or the outer zone, then the system determines if the target cylinder is in either the inner zone or the outer zone. If the target cylinder is in either the inner zone or the outer zone, then the system seeks the current head to the middle zone and then performs the head switch. If the target cylinder is in the middle zone, then the system seeks the current head to the target cylinder and then performs the head switch. If the current cylinder is in the middle zone, then the system performs the head switch without seeking. After the head switch, the system seeks the target head to the target cylinder.
Abstract:
A system for halting operation of a hard disk controller when a write operation occurs during a servo positioning error condition including a memory cell for retaining an indication of whether a write operation occurred during the previous servo sector. A memory cell, such as a flip flop, is set on any occurrence of a write operation. With the reading of a next servo field, the output of the first flip flop is latched to a second flip flop. During a present servo sector, a servo positioning error signal is logically AND'ed with a write gate active signal where the write gate active signal is enabled if write gate is active in the present servo sector or write gate was active in the previous servo sector (as indicated by the output from the second flip flop.
Abstract:
Interpolator and decimator apparatuses and methods are improved by the addition of an elastic storage element in the signal path. In one exemplary embodiment, the elastic element comprises a FIFO which advantageously allows short term variation in sample clocks to be absorbed, and also provides a feedback mechanism for controlling a delta-sigma modulated modulo-N counter based sample clock generator. The elastic element combined with a delta-sigma modulator and counter creates a noise-shaped frequency lock loop without additional components, resulting in a much simplified interpolator and decimator.
Abstract:
A method is for decoding a pulse signal modulated through a transmitted reference modulation scheme. The modulated pulse signal may include, repetitively, a reference pulse followed by an information pulse delayed with a delay. The method may include subtracting or adding from the modulated pulse signal, a version of the modulated pulse signal delayed with the delay for obtaining a processed signal, and performing a non-coherent detection on the processed signal.
Abstract:
A two terminal device which can be used for the rectification of the current. Internally it has a regenerative coupling between MOS gates of opposite type and probe regions. This regenerative coupling allows to achieve performance better than that of ideal diode.
Abstract:
A rectifier building block has four electrodes: source, drain, gate and probe. The main current flows between the source and drain electrodes. The gate voltage controls the conductivity of a narrow channel under a MOS gate and can switch the RBB between OFF and ON states. Used in pairs, the RBB can be configured as a three terminal half-bridge rectifier which exhibits better than ideal diode performance, similar to synchronous rectifiers but without the need for control circuits. N-type and P-type pairs can be configured as a full bridge rectifier. Other combinations are possible to create a variety of devices.
Abstract:
A resonant power converter for ultra-efficient radio frequency transmission and associated methods. In one exemplary embodiment, the invention is digitally actuated and uses a combination of a noise-shaped encoder, a charging switch, and a high-Q resonator coupled to an output load, typically an antenna or transmission line. Energy is built up in the electric and magnetic fields of the resonator, which, in turn, delivers power to the load with very little wasted energy in the process. No active power amplifier is required. The apparatus can be used in literally any RF signal application (wireless or otherwise), including for example cellular handsets, local- or wide-area network transmitters, or even radio base-stations.