Abstract:
The present invention concerns a method for correcting a frequency shift on symbols received by a receiver, each symbol being composed of N samples and of a cyclic prefix of a predetermined number Δ samples, the Δ samples being a copy of Δ samples of the N samples. The receiver: - calculates for each symbol, a correlation between at most the Δ samples of the cyclic prefix and the at most Δ samples among the last samples, - averages the correlations over a number of symbols and determines one smooth frequency shift estimation for each averaged correlation, - calculates an exponential from the smooth frequency shift estimation, - delays the received symbols by a delay, - multiplies the exponential by the delayed received symbols.
Abstract:
A method for transmitting measurement data 28a comprise the steps of: receiving measurement data 28a in a first communication module 22a; time stamping the measurement data 28a in the first module with a time tag 34; transmitting the measurement data 28a to a second communication module 22b via a packet switched data network 24; and outputting the transmitted measurement data 30a after a predefined delay time Δt D after the time stamping of the measurement data 28a.
Abstract:
A system and method for transmitting and recovering external clock signals over links of a DSL system in which the external clock signals are used to synchronize transmitted physical layer signals from a CO of a DSL system and said external clock signals are derived from the received physical layer signals at an RT/CPE location of a DSL system. A clock recovery subsystem located at both the CO and the RT/CPE comprises a clock monitor circuit in communication with a Phase Lock Loop circuit. The clock monitor circuit at the RT/CPE is able to derive clock signals from the received physical layer signals and select one of said derived clocks to which a local reference clock at the RT/CPE is synchronized. The synchronized local reference clock, which can exist even when there are no valid derived clocks, may be used to transmit pseudowire frames (e.g., TDM data over Ethernet).
Abstract:
An integrated circuit device includes a delay circuit, sampling circuit and delay control circuit that cooperate to carry out adaptive timing calibration. The delay circuit generates a timing signal by delaying an aperiodic input signal for a first interval. The sampling circuit samples a data signal in response to the timing signal to generate a sequence of data samples, and also samples the data signal in response to a phase-shifted version of the timing signal to generate a sequence of edge samples. The delay control circuit adjusts the first interval based, at least in part, on a phase error indicated by the sequence of data samples and the sequence of edge samples.
Abstract:
A method and apparatus for dynamically compensating for delay mismatch between a supply signal and an input signal of a power amplifier in polar modulation transmitters. One exemplary polar modulation transmitter according to the present invention comprises a power amplifier, a phase modulator, a regulator, a delay tracking circuit, and a delay circuit. The phase modulator derives the amplifier-input signal responsive to one or more phase signals, while the regulator derives the amplifier supply signal responsive to an amplitude signal. Based on the amplitude signal and the amplifier supply signal, the delay tracking circuit tracks an observed amplitude path delay. The delay circuit adjusts a path delay associated with the phase signal, responsive to the observed amplitude path delay, to compensate for the delay mismatch.
Abstract:
Die Add-DropEinrichtung enthält einen Regelkreis mit einem Phasenvergleicher (6), einem Regler (9) und einem einstellbarem optischen Laufzeitglied (8), das ein einzufügendes AddSignal (ES A ) derart verzögert, dass es in den freien Zeitschlitz eines empfangenen optischen Multiplex Signals (MS E ) eingefügt werden kann.
Abstract:
Systems and methods are disclosed to provide static and/or dynamic phase adjustments to a data signal relative to a clock signal. For example, the data signal may be delayed by a coarse delay and/or a fine delay to match the timing of the clock signal independently for each input path (e.g., per input pad). The delay may be as a function of positive and/or negative clock edges.
Abstract:
A method of beam forming is provided for an appliqué intelligent antenna system. The appliqué system uses a watchdog function to monitor broadcast channels of an existing mobile wireless base station to which it is attached. The appliqué system synchronizes itself in frequency and time to the base station. In GSM timing delays are used to prevent collision of timeslots from various mobile terminals. The appliqué system uses this time delay mechanism to compensate for its own processing delays so that its presence is transparent to the existing base station. Angle of arrival calculations are made to determining beamforming parameters. The antenna of the four element antenna system are separated by is (5 1)/2 times the wavelength. Angle of arrival for the strongest uplink multipath signal are used to direct the downlink beam.