A radio frequency (RF) front end chip in a phased array antenna panel for transmitting a modulated circularly-polarized signal is disclosed. The RF front end chip includes an oscillator providing an angular speed modulation signal to a quadrature generation block, the quadrature generation block providing an in-phase signal and a quadrature signal based on the angular speed modulation signal, a first amplifier receiving the in-phase signal and a data signal, and providing a modulated horizontally-polarized signal, and a second amplifier receiving the quadrature signal and the data signal, and providing a modulated vertically-polarized signal, where a modulated circularly-polarized signal is generated based on the modulated horizontally-polarized signal and the modulated vertically-polarized signal. The angular speed modulation signal controls an angular speed of the modulated circularly-polarized signal. The data signal is encoded by the angular speed modulation signal.

A heart generated signal is provided by a heart sensor of a mobile device to an analog to digital (A/D) converter for A/D converting the sensor provided signal. The A/D converted heart signal is processed to provide heart rate. The heart rate is recorded or stored in the mobile device or is transmitted in a wireless communication system. The mobile device receives sensor provided Electro Cardiogram (ECG) signal. The ECG signal is stored or is provided to an interface unit. The mobile device has transceivers for receiving and transmitting Orthogonal Frequency Division Multiplexed (OFDM) signals and for modulating and transmitting spread spectrum baseband signals. The spread spectrum baseband signals have cross-correlated in-phase and quadrature-phase filtered baseband signals.

A low frequency ultrasonic communication system includes: a low frequency ultrasonic transmitting apparatus configured to transmit data using a low frequency ultrasonic wave; and a low frequency ultrasonic receiving apparatus configured to recover the data by processing a low frequency ultrasonic reception signal transmitted from the low frequency ultrasonic transmitting apparatus. In communication between the transmitting apparatus and the receiving apparatus, modulation is performed using a DPSK scheme, and FEC coding is used to perform channel coding before the modulation.

A system and method employ an exclusive-OR gate having a first input configured to receive an RF carrier signal having an RF carrier, and a second input configured to receive a square wave signal having a square wave frequency, to output to a signal processing channel under test a binary phase shift keying (BPSK) signal comprising the RF carrier signal modulated by the square wave signal. A digital signal processor is configured to receive from the signal processing channel in-phase (I) and quadrature-phase (Q) data produced by the signal processing channel in response to the BPSK signal, and to process the I and Q data to determine an amplitude response and phase response of the signal processing channel as a function of frequency.

High resolution tuning of the phase for active load modulation (ALM) in a near field communication (NFC) system is desirable for optimizing the load modulation amplitude. The present disclosure describes that, in one embodiment, high resolution tuning of the phase can be achieved by adjusting the attenuation factor of a radio frequency (RF) attenuator in the NFC system.

High resolution tuning of the phase for active load modulation (ALM) in a near field communication (NFC) system is desirable for optimizing the load modulation amplitude. The present disclosure describes that, in one embodiment, high resolution tuning of the phase can be achieved by adjusting the attenuation factor of a radio frequency (RF) attenuator in the NFC system.

A transmission apparatus for a wireless device, comprising: an antenna for receiving an original signal and for backscattering a modulated signal containing information from the wireless device; a variable impedance coupled to the antenna, the variable impedance having an impedance value; a delta-sigma modulator coupled to the variable impedance for modulating the impedance value, and thereby a backscattering coefficient for the antenna, in accordance with the information to generate the modulated signal; and, a decoder coupled to the delta-sigma modulator for generating the impedance value from the information.

A shared radar and communication system for a vehicle includes capabilities for radar detection and communication with vehicles equipped with similar systems. The radar system is equipped with pluralities of transmit antennas and pluralities of receive antennas. The radar transmits a signal modulated with spread codes that are information bits. A receiver discriminates the signals sent from own transmitters and multiple reflections to detect objects of interest. In addition, the receiver discriminates signals transmitted from different systems on other vehicles. This requires the receiving system to have knowledge of the codes transmitted by the other vehicle. The receiving system determines the information bits sent by the other vehicle. If multiple radar systems on multiple vehicles use different sets of codes (but known to each other), the multiple systems can create a communication infra-structure in addition to radar detection and imaging.

Provided is a precoding method for generating, from a plurality of baseband signals, a plurality of precoded signals to be transmitted over the same frequency bandwidth at the same time, including the steps of selecting a matrix F[i] from among N matrices, which define precoding performed on the plurality of baseband signals, while switching between the N matrices, i being an integer from 0 to N−1, and N being an integer at least two, generating a first precoded signal z1 and a second precoded signal z2, generating a first encoded block and a second encoded block using a predetermined error correction block encoding method, generating a baseband signal with M symbols from the first encoded block and a baseband signal with M symbols the second encoded block, and precoding a combination of the generated baseband signals to generate a precoded signal having M slots.

For generating quantized signals, a quantized phase domain related to quantized phases of an input signal is generated. Vectors that the input signal may occupy are calculated based on the quantized phase domain. A first quantized phase of a first component of the input signal is generated per the quantized phase domain, and a second quantized phase of a second component of the input signal is generated per the quantized phase domain.