摘要:
The present invention relates to a modulator for a digital amplifier and a device comprising such a modulator and a digital amplifier.The modulator (100) comprises a pulse shaper (110) and a control unit (120) for controlling the pulse shaper (110) to convert an input signal into a bit stream (130) configured for a digital amplifier which encodes an amplitude value per clock of a carrier signal. The pulse shaper (110) can represent a respective amplitude value of the input signal with different bit patterns. The bit pattern respectively used by the pulse shaper is determined by the control unit (120) by means of a corresponding, associated control command. The modulator (100) is characterized in that in the control unit (120) an assignment (160) of the control commands to associated amplitude values resulting from amplification of the associated bit patterns with the digital amplifier (400) is stored or at least is provided in that the control unit (120) selects a control command per clock by means of the assignment (160) and the amplitude value of the input signal and drives the pulse shaper (110) accordingly.
摘要:
The present invention relates to a single frequency synthesizer based FDD transceiver. A single frequency synthesizer generates and provides a carrier frequency so that frequency up-conversion and frequency down-conversion can be performed at the time of transmission and reception. Accordingly, the area, power consumption, and design complexity of the entire system can be reduced, and the performance of the system can be improved.
摘要:
A method of performing complementary mixing may include performing an exclusive OR (XOR) function with respect to an I-channel symbol based on an oscillator signal to produce an I-channel output signal with bits that alternate between the I-channel symbol and a complement of the I-channel symbol in response to the oscillator signal rising and falling. The method may also include performing the XOR function with respect to a Q-channel symbol based on the oscillator signal to produce a Q-channel output signal with bits that alternate between the Q-channel symbol and a complement of the Q-channel symbol in response to the oscillator signal. Further, the method may include combining the I-channel output signal and the Q-channel output signal based on adding operations performed with respect to an I-channel extra bit signal, a Q-channel extra bit signal, the I-channel output signal, and the Q-channel output signal to generate a complementary mixed signal.
摘要:
A modulator for an electrical signal comprises a data input port and a clock frequency input port. The modulator also comprises a first phase shifter for subjecting input clock frequency signals to a phase shift and adapted to keep the phase of an input clock frequency signal aligned with the phase of a data stream which is input at the data input port. The modulator also comprises a first XOR gate with an output port, to which first XOR gate said input ports of the modulator are connected, by means of which a BPSK signal is created at the output port when a first data stream is connected to the data input port and a first clock frequency signal is connected to the clock frequency input port.
摘要:
A method for communication between near field communication (NFC) devices includes generating a transmission signal, an in-phase local oscillator signal, and a quadrature local oscillator signal from edges of an input clock signal. The method further includes mixing a load modulated signal with the in-phase local oscillator signal to generate an in-phase baseband signal. The method further includes mixing the load modulated signal with the quadrature local oscillator signal to generate a quadrature baseband signal. The method further includes adjusting a phase delay of at least one of the in-phase local oscillator signal or the quadrature local oscillator signal in response to a first signal strength of the in-phase baseband signal and a second signal strength of the quadrature baseband signal.
摘要:
A signal converter for converting a start signal into an end signal includes means for copying the start signal to obtain a plurality of copied start signals, wherein a copied start signal may be fed into a processing branch as a branch signal. Further, the signal converter includes a first branch processing means in a first processing branch for processing a first branch signal according to a first processing regulation to obtain a first processed branch signal. Further, the signal converter includes a second branch processing means in a second processing branch for processing a second branch signal according to a second processing regulation to obtain a second processed branch signal, wherein the second processing regulation is different from the first processing regulation and wherein the first processing regulation and the second processing regulation are implemented to cause a low-pass polyphase filtering of the copied start signals. Finally, the signal converter includes selection means for sequentially selecting the first processed branch signal and then the second processed branch signal in order to obtain the end signal.
摘要:
A direct division modulator is provided. The direct division modulator includes a symbol mapper converting the input data from a binary bitstream to a desired frequency deviation, such as where the frequency deviation data encodes the information from the bitstream. A converter generates a divide value using the desired frequency deviation information, and a summer adds an average value to the divide value. A converter quantizes the divide value and shapes quantization noise associated with the quantized divide value. A divider modulates a reference signal with the quantized divide value and generates an output signal.
摘要:
A transmitter digital signal processor (DSP) circuit has a transmit frequency represented by n-bit data output from a look up table (LUT). The n-bit data is outputted to an n-bit accumulator structured to overflow at a rate based on the output n-bit data to output a phase. The circuit further has device structured to add an n-bit signed constant to the accumulator to offset the frequency represented by the n-bit data output from the LUT. A transceiver on a semiconductor chip may include as part of a transmitter circuit, a transmit DSP circuit that has the LUT, accumulator and device providing an n-bit signed constant to the accumulator to offset a transmit frequency in order to allow a receiver circuit on the transceiver to communicate directly with the transmitter circuit, and thus allowing testing of the transceiver.
摘要:
A FIR chip is used in a wireless subscriber unit. The subscriber unit includes a processor for transcoding an input signal to provide digital input symbols. A received output signal is demodulated. Digital output symbols are synthesized from the demodulated output signal processor and filtered digital input symbols are provided. An internal address decoder decodes to allow the processor to access internal functions of the FIR chip. A control and status register allows the processor to read the status of and control the internal functions of the FIR chip. A FIR filter filters the digital input symbols. A transmit timer controls timing which allows the processor to control the FIR filter. A receive timer generates timing signals for timing transcoding operations and synthesizing operations connected to the processor.
摘要:
A subscriber unit has a processor. The processor provides an output phase signal corresponding to a selected output digital frequency. A tuning register buffers the phase signal. A lookup table has two sets of predefined stored values pertaining to the amplitude of a signal for a single quadrant. The predefined stored values comprise coarse angle approximations and fine angle approximations. A sine and cosine generator receives the phase signal and generates sine and cosine waveforms utilizing amplitude values obtained from the lookup table. The phase signal includes phase data and specifies the quadrant and the algebraic sign of the phase data. The sine and cosine generator accessing the lookup table differently depending upon the quadrant and sine of the phase data, such that the lookup table provides an amplitude value from the sets of predefined stored values based on the phase data. A modulator combines the sine and cosine waveforms to produce the selected output digital frequency and modulates digital frequency.