An apparatus and a method. The apparatus includes a channel estimation (CE) module, including a first input for receiving pilot resource element (RE) observations, a second input for receiving data RE observations, a third input for receiving log-likelihood ratios (LLRs), and an output; a detector, including a first input connected to the output of the CE module, a second input for receiving data RE observations, and an output connected to the third input of the CE module; and a decoder, including an input connected to the third input of the CE module, and an output.

A wireless transmitter, comprises a frame generator configured to generate a frame by including an auxiliary preamble, an auxiliary syncword, a guard, a preamble, an address, a packet control, a payload and a CRC; a modulator communicatively coupled to the frame generator and configured to modulate the frame according to a variable transmission rate and include the transmission rate in the auxiliary syncword; and a RF front end communicatively coupled to the modulator and configured to transmit the modulated signal to a receiver.

A method for allocating bandwidth to communication according to a first communication protocol, the method comprising identifying bandwidth that is allocated to a communication channel for communication according to a second communication protocol and which forms a guard band of the communication channel and allocating the identified bandwidth to communication according to the first communication protocol, said allocation being performed non-uniformly across the identified bandwidth such that an allocation of a first portion of the identified bandwidth, which is located closer to a communication according to the second communication protocol than a second portion of the identified bandwidth, is constrained to a greater extent than an allocation of the second portion of the identified bandwidth.

Provided is a method for eliminating an interference operating on a receiver of a transmitter in a communications system, which includes transmitting at least one user signal; changing user phase information to be separated from interference phase information by a preset difference, when receiving the user phase information of the user signal and the interference phase information of an interference signal from at least one receiver; and transmitting at least one other user signal according to the changed user phase information.

Digital mobile communications devices and methods for mobile peer to peer direct communications. Processing a touch screen generated signal into a processed touch screen control signal for controlling mobile devices. Processing fingerprint signal for authenticating a user of a mobile device. Processing in a mobile device a motion detector generated signal into a motion detector generated control signal, for navigation control of mobile device. Modulation and demodulation, transmission and reception of one Orthogonal Frequency Division Multiplexed (OFDM) signals and conversion of the received OFDM signal into a different OFDM signal. Received spread spectrum signals from 3G or 4G cellular systems are converted into OFDM signals and transmitted in a wireless network, e.g. a Wi-Fi network. Received OFDM signals, received in a first RF frequency band, are demodulated and in a repeater mode are re-transmitted in a cellular system or network in a second OFDM radio frequency band. One or more receivers and demodulators for receiving demodulating and processing received signals into location finder information. A video camera in mobile device generates video signal and transmits video signal with location finder information signal.

An improved coherent communication scheme is provided. The coherent communication scheme encodes both classical and quantum information simultaneously using isolated groups of states: classical information is represented by different groups and can be decoded deterministically; and quantum information is represented by highly overlapped states within the same group, thus guaranteeing security. Decoding includes projecting the detection results at the receiver to one of the distinguishable encoding groups first, which allows the classical information to be read out, and then generating a quantum key from the residual randomness. This communications scheme enables simultaneous classical communication and QKD over the same communication channel using the same transmitter and receiver, opening the door to operate QKD in the background of classical communication and at negligible costs.

The method of phase modulating a carrier wave involves creating a set of signals s.sub.h(t) constituted by a carrier wave of frequency f.sub.C and of phase (t)=h.sub.0(t) that is modulated in time t in such a manner that s.sub.h(t)=cos(2f.sub.Ct+h.sub.0(t)), where h is an integer and where .sub.0(t)=2 arctan((tt.sub.0)/w.sub.0). The modulation corresponds to a single phase pulse centered on a time t.sub.0 of characteristic duration w.sub.0 that is positive, and incrementing the phase of the signal s.sub.h(t) by the quantity h2, in such a manner as to generate a single sideband frequency spectrum directly. The carrier wave may be of electromagnetic type or of acoustic type. The method applies in particular to transporting binary information by single sideband phase coding, to generating single sideband orthogonal signals, to detecting single sideband phase coded multiple-level digital signals, to transmitting single sideband phase coded binary signals in-phase and out-of-phase, and to single sideband combined amplitude-and-phase modulation.

In some embodiments, a DFE including: an input terminal configured to receive an input signal carrying a plurality of symbols; an adder circuit coupled to the input terminal of the DFE; a plurality of comparator circuits configured to receive respective threshold signals; a plurality of slicer circuits coupled to respective comparator circuits of the plurality of comparator circuits; and a plurality of multiplier circuits coupled to respective slicer circuits of the plurality of slicer circuits, the plurality of multiplier circuits configured to multiply respective correction coefficients of a plurality of correction coefficients times respective outputs of respective slicer circuits to produce respective multiplication results of a plurality of multiplication results, where: the adder circuit is configured to subtract the plurality of multiplication results from the input signal, and the plurality of correction coefficients are independently adjusted based on a previously received symbol.

Digital mobile communications devices and methods for processing fingerprint signal for authenticating a user of a mobile device. Processing a touch screen generated signal into a processed touch screen control signal for controlling mobile devices. Processing in a mobile device a motion detector generated signal into a motion detector generated control signal, for navigation control of mobile device. Modulation and demodulation, transmission and reception of spread spectrum signals, Orthogonal Frequency Division Multiplexed (OFDM) signals and conversion of spread spectrum signals into OFDM signals. Received spread spectrum signals from 3G cellular systems are converted into OFDM signals and transmitted in a wireless network, e.g. a Wi-Fi network. Received OFDM signals, received in a first RF frequency band, are demodulated and in a repeater mode are re-transmitted in a cellular system or network in a second OFDM radio frequency band. One or more receivers and demodulators for receiving demodulating and processing received signals into location finder information. A video camera in mobile device generates video signal and transmits video signal with location finder information signal.

A wireless transmitter, comprises a frame generator configured to generate a frame by including an auxiliary preamble, an auxiliary syncword, a guard, a preamble, an address, a packet control, a payload and a CRC; a modulator communicatively coupled to the frame generator and configured to modulate the frame according to a variable transmission rate and include the transmission rate in the auxiliary syncword; and a RF front end communicatively coupled to the modulator and configured to transmit the modulated signal to a receiver.