Sequans

About: Sequans is a company organization based out in Reading, United Kingdom. It is known for research contribution in the topics: Communication channel & MIMO. The organization has 73 authors who have published 126 publications receiving 1066 citations.

Method for estimating a received signal and corresponding device

Abstract: A method and apparatus for estimating a transmission channel in a receiver of an OFDMA signal formed by a plurality of carriers modulated by data elements and distributed in the time-frequency domain in successive symbols, the plurality of carriers including pilot carriers, modulated by reference data elements known by receivers The method includes: receiving a signal comprising a series of n symbols covering at least one resource block; making an initial channel estimation by identifying the pilot carriers included in the series of n symbols; determining diagonal entries of p frequency domain channel matrices G (x) for estimating the channel for at least x symbols among the n symbols, the x symbols being pilot symbols; determining, in the frequency domain, at least some non diagonal entries for each frequency domain channel matrix G of the n symbols from the determined diagonal entries of the x frequency domain channel matrices G (x)

Driving circuit for single crystal RTC and RF clock

Abstract: A crystal driving circuit comprising a circuit input node and a circuit output node, a high power amplifier having a power consumption of more than 100 μW, a low power amplifier comprising a power consumption less than 10 μW, the circuit being arranged to selectively isolate the high power amplifier and associated load capacitance from the circuit input node and the circuit output node.

Channel estimation method using an improved Expectation Maximization (EM-)Algorithm

Abstract: The invention relates to a channel estimating method in an orthogonal frequency division multiplexing (OFDM) system transmitting signals over said channel, wherein an OFDM symbol of each of said signals has at least one null subcarrier set in its defined bandwidth, According to the invention, said method comprises the following steps: - obtaining at least one initial channel estimate over at least one OFDM symbol of a received signal; - processing said at least one initial channel estimate for delivering at least one soft information in a form of a complete matrix; - improving said at least one initial channel estimate by performing a truncated singular value decomposition of a partial FFT matrix, wherein said partial FFT matrix comprises only the first LDP columns and the rows NDP of an FFT matrix of said complete matrix, said NDP rows corresponding to modulated subcarriers of received signal, including data and pilot symbols and excluding said at least one null subcarrier, delivering an improved channel estimate.

Interference reduction method

Abstract: A method for calibrating signal transmission equipment. The equipment includes at least two signal transmission subsystems, a first subsystem implementing a first signal transmission technology and a second subsystem implementing a second signal transmission technology. The method includes transmitting, by the first subsystem, a signal at a predetermined transmission power; measuring, by the second subsystem, an amount of noise perceived on at least one channel associated with the second subsystem; and recording, in a data structure, the amount of noise for the at least one associated channel.

OFDM synchronization evaluation

Abstract: A method of evaluating OFDM synchronization between a transmitter and a receiver, the method carried out at the receiver and comprising, obtaining a non-coherent channel power estimate, obtaining a coherent channel power estimate, comparing the two estimates, and determining whether the receiver and the transmitter are synchronized based on the comparison.