Abstract: A modulation device uses two base signal axes including a cosine function and two base signal axes including a sine function to modulate bit information and generate a modulation symbol. Accordingly, the frequency efficiency characteristic is improved while maintaining a great power efficiency characteristic.

Abstract: A method for transmitting information using a sequence is disclosed. According to an embodiment, the method includes the steps of generating a sequence for transmitting data or control signals, performing phase modulation for indicating additional information on partial elements among a plurality of elements configuring the sequence, and transmitting the phase modulated sequence.

Abstract: The invention relates to a space-time coding method for a MIMO-UWB system with P antennas using information symbols belonging to an M-PPM, where M is a multiple of P. The modulation alphabet is partitioned into P sub-alphabets corresponding to successive ranges of modulation positions. An extension of the initial alphabet is obtained by forcing the information symbols to belong to some sub-alphabets, thereby increasing the binary rate of said system.

Abstract: A power tuning method determines values of a magnitude control signal that controls the magnitude of an amplitude-modulated power supply signal applied to a power supply port of a power amplifier of a polar transmitter and an amplitude control signal that controls the amplitude of a constant-envelope phase-modulated signal applied to a radio frequency input port of the power amplifier necessary to set the output power of the polar transmitter to a target output power. The method is repeated and performed for a plurality of different target output powers. Output-power-level dependent power control parameters calculated from the applied method are used to set the values of the magnitude control and amplitude control signals during normal operation.

Abstract: Techniques are disclosed for detecting a packet. One technique includes sampling a received signal to produce a sequence of samples wherein the sequence of samples includes a plurality of subsequences of samples; cross correlating the subsequences of samples with a known form of the subsequence to produce cross correlations; self correlating the cross correlations to produce a plurality of self correlations; summing the self correlations; and processing the sum of the self correlations.

Abstract: A data transmitting apparatus performs symbol mapping on each of first and second input data to generate a plurality of first and second modulation data symbols, performs inverse fast Fourier transform (IFFT) on the plurality of first and second modulation data symbols to convert the same into first and second real signals of a time domain from a frequency domain, angle-modulates the first and second real signals, and transmits the same to a data receiving apparatus. Thus, a peak-to-average power ratio (PAPR) can be lowered, while the same data transfer amount as that of the general OFDM data transmitting apparatus is maintained.

Abstract: System(s) and method(s) are provided to transmit simultaneously a first and a second communication channel in a single-carrier waveform format with disparate error rate requirements. First channel and second channel are coded individually to form an alphabet for a first and second constellation. Prior to transmission, bits of information of the first and second channels are modulated with a hierarchical modulation constellation is generated through a combination of a first a second constellation; each constellation is assigned a configurable weight (e.g., a “hierarchic weight”) that is expressed in terms of a configurable energy ratio. The energy ratio determines the resilience of bits associated with the first and second channel. Bit mapping within the first and second constellation provides redundancy to mitigate error rate within each quadrant of the hierarchical constellation.

Abstract: This disclosure relates systems and methods for a high bandwidth modulation and transmission of communication signals.

Abstract: A non-linear FM pulse compression system includes a non-linear FM transmitter adapted to receive an input signal and transmit an output signal. The non-linear FM transmitter is adapted to modulate the frequency of the output signal by at least one of the following: increasing the frequency of the output signal as a logarithmic function of the frequency of samples in the input signal; modulating the frequency of the output signal in inversely proportional relationship to the frequency of samples in the input signal; and modulating the frequency of the output signal according to a random permutation of the frequency of the input signal. At least one antenna interfaces with the non-linear FM transmitter. A non-linear FM receiver interfacing with the at least one antenna. The non-linear FM receiver is adapted to auto-correlate the output signal with a return signal.

Abstract: A transmission signal processing method is provided, for generating a first OFDM modulation signal and a second OFDM modulation signal which are transmitted in an identical frequency band, by utilizing a first antenna for transmitting the first OFDM modulation signal and by utilizing a second antenna for transmitting the second OFDM modulation signal. The method includes a step of generating the first OFDM modulation signal and the second OFDM modulation signal utilizing a plurality of OFDM modulation signal generators, and a step of outputting the first OFDM modulation signal to the first antenna and the second OFDM modulation signal to the second antenna.

Abstract: A transmission circuit switches a bias circuit without allowing a power amplifier to enter a non-bias state. A first bias circuit supplies a first bias signal to a power amplifier, and a second bias circuit supplies a second bias signal to the power amplifier. A first delay circuit delays the switching of an operation of the first bias circuit using a first delay time, and a second delay circuit delays the switching of an operation of the second bias circuit using a second delay time. The first bias circuit and the second bias circuit are both simultaneously operated for a predefined time period, in order to prevent a transistor for amplification from entering a non-bias state when switching an operation mode of the power amplifier.

Abstract: An object is to provide a semiconductor device which operates normally even when the communication distance is extremely short, while the maximum communication distance is maintained, and which can make amplitude of a response waveform large even when a large amount of electric power is supplied to the semiconductor device and a protection circuit operates. The object is achieved with a semiconductor device including a first modulation circuit and a second modulation circuit each of which performs load modulation by an input signal, a detection circuit which determines an output signal by electric power supplied externally, a protection circuit which is controlled by the output signal of the detection circuit, and a modulation selecting circuit which switches the first modulation circuit and the second modulation circuit depending on the output signal of the detection circuit.

Abstract: A device article and method for an open loop calibrated phase wrapping phase modulator. A tapped delay line may provide a coarse resolution for one or more phases of a signal. A phase multiplexer may receive one or more coarse phases from the tapped delay line and select a coarse phase to send to the digitally controlled delay line. A digitally controlled delay line may provide a fine resolution to the coarse phase from the phase multiplexer.

Abstract: A digital signal transmitting apparatus that prevents occurrences of highness and lowness in error tolerance due to bit positions without raising the redundancy and without retransmittal. In the digital signal transmitting apparatus, a bit interchanging part (103) uses rate match information (105) to interchange bit positions such that a bit inserted by a rate match part (102) is placed at the bit position of a low error tolerance in a single symbol to be multilevel modulated. Moreover, the bit interchanging part (103) also uses the rate match information (105) to interchange bit positions such that another encoded bit, in which the bit punctured by the rate match part (102) is the same as the bit prior to encoding thereof, is placed at a bit position of a high error tolerance in a single symbol to be multilevel modulated.

Abstract: A polar transmitter includes a phase monitoring unit for monitoring input modulating data. When a phase transition exceeds a phase transition threshold, the phase monitor unit can signal an amplitude negation unit to invert the amplitude data coupled to the polar amplifier. The phase monitoring unit can also add an offset to the phase data that is provided to a frequency synthesizer. In another embodiment, when the phase transition threshold is exceeded, the phase monitoring unit can trigger inverting differential frequency data coupled to the polar amplifier. In one embodiment, the phase offset and the amplitude negation are applied until a second phase transition value exceeding the phase transition threshold is detected. If such an event is detected, then the input amplitude data is no longer inverted and the phase offset value is no longer added to the modulating data.

Abstract: Phase shifting circuitry is provided for phase shifting at least one of first and second quadrature components of a data signal. The circuitry includes a first phase shifter adapted to phase shift, by a first phase angle, the first quadrature component by adding together weighted versions of the first and second quadrature components.

Abstract: An encoder encodes sound data and the like to generate a binary signal. A mapper converts the binary signal into a four-level symbol and outputs the four-level symbol. A base band filter includes a root raised cosine filter and a sinc filter. The base band filter blocks a predetermined frequency component of a symbol to shape the symbol into a waveform signal and outputs the waveform signal shaped. An FM modulator transmits a signal subjected to FM modulation according to a magnitude of an amplitude of a waveform signal to a receiving unit. When a symbol of ±3 is outputted from the mapper, a frequency shift of a signal transmitted from the FM modulator has a predetermined value in a range of ±0.822[kHz] to ±0.952[kHz]. This makes it possible to provide a modulating apparatus, a mobile communication system, a modulating method, and a communication method that use a modulating method that can conform to the FCC rule to be enforced in 2005 without using a linear power amplifier.

Abstract: In an envelope comparison embodiment, a delay calibrator produces a delay signal based on a comparison of a feedback signal and an envelope component of the transmitted signal. A down-converter produces the feedback signal from an outgoing modulated RF signal based on at least one local oscillation. Envelope detectors in the delay calibrator and the envelope signal path are operably coupled to a summing node that produces a delay error signal based on a temporal difference between the two envelopes. One embodiment includes phase detectors to detect and adjust the zero crossings of the feedback signal and the envelope signal path. As the delay mismatch between the envelope signal path and the phase signal path increases, the power spectrum increases in adjacent communication channels. A mask margin measurement technique measures the power level in an adjacent channel and adjusts the envelope path delay accordingly.

Abstract: Test signal generator (3) generates test signals represented, by four points, which comprise two sets of two points positioned in point symmetry with respect to the origin of an I/Q orthogonal coordinate system. Envelope detector (8) detects the amplitude of an envelope of the output signal from an orthogonal modulator when the test signals represented by four points are generated, and outputs a signal proportional to the square of the amplitude. Comparing unit (9) calculates an average value of output signals from envelope detector ( ) when the test signals represented by the two points of each set are generated. Controller (10) adjusts the amplitudes and/or phases of the test signals so that the average values produced when the test signals represented by the two sets of the two points are generated are equal to each other, and calculates an I/Q mismatch quantity based on the adjusted results.

Abstract: Disclosed is a binary signal modulator for minimizing deterioration of receiving performance caused by phase error. The binary signal modulator receives binary signals, and converts the binary signals into complex symbols according to a predetermined mapping relation. Here, the mapping relation is generated when a plurality of mapping symbols are arranged on a plurality of trajectories so that the distance between the mapping symbols is greater than or equal to a predetermined distance and the phase between the mapping symbols is greater than or equal to a predetermined angle from among the trajectories starting from a plurality of points on the complex plane, and a distance between the trajectories is greater than or equal to the minimum distance from among the distances between the points.

Abstract: A new pulse shape for CPM is introduced which is obtained by a linear combination of well-known RC and REC pulse shapes. The new pulse shape addresses the tradeoff between the width of the PSD main lobe and the rate of decay of the side lobe to improve the coded performance of multi-carrier systems affected by ACI. Also, a methodology is proposed to design and evaluate the performance of the new pulse shape for multi-carrier, coded systems based on the modulation constrained capacity. Furthermore, a binary convolutional code and the CPM modulator are concatenated using an S-random bit interleaver to lower the error floor. Finally, Laurent representation of the new pulse shape is suggested such that by retaining only the principal pulses at the receiver, complexity of the receiver can be reduced.

Abstract: A programmable hybrid transmit baseband module includes a wireless protocol conversion module, a set of modules, and a mode select module. The wireless protocol conversion module is operable to convert outbound data into a complex signal having an in-phase (I) signal component and a quadrature (Q) signal component. The set of modules is operable to generate an offset adjusted normalized I signal component, an offset adjusted normalized Q signal component, and corrected amplitude modulation data, wherein each of the normalized I and Q signal components includes phase modulation data. The mode selection module is operable to output the I and Q signal components when the programmable hybrid transmit baseband module is in a first mode; and output the offset adjusted normalized I and Q signal components and the corrected amplitude modulation data when the programmable hybrid transmit baseband module is in a second mode.

Abstract: A communication apparatus for a continuous phase modulation signal. The communication apparatus includes a first processing unit configured to generate first information of the continuous phase modulation signal using first symbol data; a symbol converting unit configured to convert the first symbol data into second symbol data or convert the second symbol data into the first symbol data; a symbol storage unit configured to store the second symbol data; a second processing unit configured to second information of the continuous phase modulation signal using the second symbol data stored in the symbol storage unit; a third processing unit configured to generate third information of the continuous phase modulation signal using a modulo operation of an integer related to a modulation index; and an output unit configured to add an output from the third processing unit and an output from the first processing unit and generate the continuous phase modulation signal.

Abstract: In a high-precision signal detection apparatus and method for a high-speed receiver, signal detection occurs asynchronously of the incoming data. A comparison clock is generated by an oscillator whose effective capacitance is varied by a second, lower speed oscillator connected to the capacitance. This prevents the asynchronous sampling that occurs in a zero-crossing position in the incoming data from remaining in that position in subsequent sampling cycles, so that a valid signal is not missed by the detector.

Abstract: An encoder encodes audio data and the like to generate a binary signal. A mapper converts the binary signal into a four-level symbol and outputs the four-level symbol. A base band filter includes a root raised cosine filter and a sinc filter. The base band filter blocks a predetermined frequency component of a symbol to shape the symbol into a waveform signal and outputs the waveform signal shape. An FM modulator transmits a signal subjected to FM modulation according to a magnitude of an amplitude of a waveform signal to a receiving unit. When a symbol of ±3 is outputted from the mapper, a frequency shift of a signal transmitted from the FM modulator has a predetermined value in a range of ±0.822 [kHz] to ±0.952 [kHz]. This makes it possible to provide a modulating apparatus, a mobile communication system, a modulating method, and a communication method that use a modulating method that can conform to the FCC rule to be enforced in 2005 without using a linear power amplifier.

Abstract: A system and method for controlling modulation. The system includes a plurality of modulators and a transmitting unit. The plurality of modulators decodes data from a data signal and also encodes the data into a clock signal. The transmitting unit transmits the encoded clock signal. According to the system and method disclosed herein, the present invention provides optimized coding efficiency while minimizing overall power consumption.

Abstract: A method is provided which improves reliability of channel estimation in a digital communication system by reducing the ambiguity in the recognition of received symbols evaluated for the channel estimation. A first plurality of bits is mapped to a modulation state according to a given Gray mapping of binary numbers to modulation states and transmitted. The plurality of bits is re-transmitted at least once, with a sub-set of bits contained in the plurality of bits inverted, and mapped to further modulation states according to the same Gray mapping. The bits to be inverted are determined in a way that the number of different vector sum results obtainable, for all combinations of bit values within the first plurality of bits, by adding vectors representing complex values of the first and further modulation states in a complex plane, is lower than the number of different modulation states within the Gray mapping.

Abstract: A transmission device of the present invention comprises: an orthogonal modulator performing orthogonal modulation on a carrier wave using an input signal comprising an in-phase signal component and an orthogonal signal component, and outputs a modulation signal to be transmitted; a detection unit detecting a carrier leaking component included in the modulation signal; a DC offset value computing unit computing a DC offset value to be added to the input signal for compensating the carrier leaking component, based on the carrier leaking component; and an abnormality judgment unit judging abnormality of the orthogonal modulator based on the DC offset value. By monitoring the DC offset value, a failure of the orthogonal modulator or an indication thereof is detected, and transmission of an abnormal modulation signal including a distortion component is prevented. An increase of the leaking power to adjacent channels, which causes the quality deterioration in adjacent radio communication lines, can be prevented.

Abstract: A multi-mode transmission system supporting OFDM and single-carrier signals is configured to perform interpolation and decimation such that the ratio of the interpolation factor to the decimation factor equals the ratio between the OFDM sampling rate and the single-carrier chip rate. A constant-envelope modulator comprises a ?/4 fixed rotator, a ?/2 continuous rotator, and in-phase and quadrature-phase analog Bessel filters. Frame formats and signaling protocols are provided for signal acquisition, synchronization, and tracking between wireless devices that employ different antenna configurations. Spreading gains are selected to compensate for different antenna gains such that the total gain (antenna gain plus spreading gain) is substantially equal for transmissions employing different beam patterns.

Abstract: Apparatus and methods for adjustment of spectral signal characteristics in polar modulators are described. A composite signal detection circuit is configured to detect when a signal trajectory of a composite signal provided to the polar modulator passes near the origin of a complex plane associated with the composite signal, and then adjusts the composite signal to pass through the origin. A spectral adjustment circuit is described to adjust AM and FM or PM components of the composite signal to reduce the deviation of an FM component of the composite signal.

Abstract: An RF transmitter includes a Cartesian to polar conversion section, a PLL, a DAC module, a mixing module, and a PA module. The Cartesian to polar conversion section converts a Cartesian based symbol stream into a polar based symbol stream. The PLL generates an oscillation when the RF transmitter is in a Cartesian mode or a phase modulated oscillation based on phase modulation information of the polar based symbol stream when the RF transmitter is in a polar mode. The mixing module mixes an analog Cartesian based signal with a local oscillation to produce a Cartesian based up converted signal when the RF transmitter is in the Cartesian mode and mixes an analog amplitude signal with a phase modulated local oscillation to produce a polar based up converted signal when the RF transmitter is in the polar mode.

Abstract: An optical homodyne communication system and method in which a side carrier is transmitted along with data bands in an optical data signal, and upon reception, the side carrier is boosted, shifted to the center of the data bands, and its polarization state is matched to the polarization state of the respective data bands to compensate for polarization mode dispersion during transmission. By shifting a boosted side carrier to the center of the data bands, and by simultaneously compensating for the effects of polarization mode dispersion, the provided system and method simulate the advantages of homodyne reception using a local oscillator. The deleterious effects of chromatic dispersion on the data signals within the data bands are also compensated for by applying a corrective function to the data signals which precisely counteracts the effects of chromatic dispersion.

Abstract: A receive frequency band interference protection system includes an input terminal for receiving an input signal and a dividing coupler coupled to the input terminal. The dividing coupler is configured to divide the input signal into a first signal and a second signal. The system further includes a first signal path and a second signal path. The first signal path includes a delay, and it is coupled to the dividing coupler and configured to receive the first signal. The second signal path is coupled to the dividing coupler and configured to receive the second signal. The second signal path includes an attenuator coupled to the dividing coupler and a predistortion linearizer coupled to the attenuator. The system further includes a combining coupler and an output terminal. The combining coupler is coupled to the first signal path and the second signal path. The combining coupler is configured to obtain a sum of the respective outputs of the first signal path and the second signal path.

Abstract: A modulation system can switch between two modulation modes. In order to comply with limits on peak power in spectral bands outside the RF operating one the transmitter is required to ramp down to a condition of minimal power. To avoid fixed ramping and trailing bits, the transmitting signal is subjected to FIR filtering. The two FIR filters are primed with a sequence using a parallel input mode before serially entering the information data.

Abstract: A method of transmitting a control channel format indicator (CCFI), also known as PCFICH (Physical Control Format Indicator Channel), in case where the length of a coded CCFI is not an integer multiple of three, including mapping a plurality of two-bit CCFI into a codebook with each component codeword having three bits; generating a sequence of codewords selected from the codebook by repeating the selected component codeword for predetermined times; generating a codeword by concatenating the sequence of the selected component codewords with the original CCFI bits; and transmitting the codeword carrying information of CCFI. The method further includes a step of generating a permutation of each of the four codewords by assigning K repetitions of the three-bit component codeword to the number of K resource units respectively and mapping remaining K bits of each of the four codewords separately to the number of K resource units.

Abstract: A multi-level pulse modulated polar transmitter and a method of generating multi-level pulse modulated RF signals carrying phase information, in conjunction with a plurality of power amplifiers, so as to enhance the bandwidth of the transmitter and to reduce spurious emission and noise while synchronizing the phase and envelope of the input signals.

Abstract: A radio receiver includes an in-phase channel and a quadrature channel, the channels being provided in parallel at a respective input with quadrature modulated radio frequency signals; and an error correction loop for detecting and correcting an imbalance in gain between at least part of the in-phase channel and a corresponding part of the quadrature channel, wherein the error correction loop comprises: a detector adapted to calculate Error_detnew=|I?|?|Q?|, where I? and Q? are the in-phase and quadrature channels respectively; a loop filter arranged to receive Error_detnew from the detector and calculate loop_filter_outnew+=Ki * Error_detnew, where Ki is the loop filter constant and loop_filter_outnew has an initial value of 1; and a multiplier arranged to receive loop_filter_outnew from the loop filter and adjust the signal of the quadrature channel by multiplying the signal by loop_filter_outnew.

Abstract: An integrated transmit circuit includes a voltage controlled oscillator (702) for generating an input frequency signal (e.g., VCO) that is provided to a divide by two quadrature generator circuit (706) which generates therefrom in-phase and quadrature clocking signals (I, IB, Q, QB) that are applied to control a plurality of transmission gates (711-718) configured in a matched switching topology (710) so as to selectively pass pulses from the input frequency signal, thereby generating interleaved LO pulses (Ø1, Ø1B, . . . Ø4, Ø4B). By applying the interleaved LO pulses to control the transmission gates (26, 28, 30, 32, 34, 36, 38, and 40) in the upmixer (720), the +I, ?I, +Q, ?Q input signals are interleaved over a plurality of phases of a carrier period to produce differential outputs (42, 44).

Abstract: An RF front-end includes a transmit adjust module, a PA module, an antenna coupling circuit, a LNA module, and a receive adjust module. The transmit adjust module adjusts coordinates of up-converted analog signals when in a first transmit mode and adjusts coordinates of a plurality of up-converted analog signals when in a second transmit mode to produce to produce multiple adjusted up-converted signals and a plurality of adjusted up-converted signals, respectively, which are subsequently amplified by the PA module. The antenna coupling circuit provides the multiple or the plurality of outbound RF signals to at least some of a plurality of antennas depending on the transmit mode and provides multiple or a plurality of inbound RF signals at least some of the plurality of antennas to the LNA module based on a receive mode. The receive adjust module adjusts coordinates of the multiple or plurality of amplified inbound RF signals based on the receive mode.

Abstract: A new coded continuous phase modulation (CPM) scheme is proposed to enhance physical layer performance of the current DVB-RCS standard for a satellite communication system. The proposed CPM scheme uses a phase pulse design and combination of modulation parameters to shape the power spectrum of CPM signal in order to improve resilience to adjacent channel interference (ACI). Additionally, it improves error rate performance at both high and low frame error rates using low complexity binary convolutional codes and S-random bit interleaving. Phase response using the proposed CPM scheme is a weighted average of the conventional rectangular and raised-cosine responses and provides optimum response to minimize frame error rate for a given data rate.

Abstract: A pulse amplitude modulation (PAM) signal generator that injects a copy of a pulse into the PAM baseband signal prior to frequency upconversion and power amplification. The pulse comprises a function of, or an extra copy of, a pulse in the PAM baseband signal. The pulse injector analyzes the PAM baseband signal for times when a predetermined threshold is exceeded and forms a pulse that is constructed and arranged to reduce the amplitude of the PAM baseband signal to a desired peak amplitude when the pulse is added to the PAM baseband signal. In other embodiments the peak-to-RMS amplitude ratio reducing methods and apparatus used to process PAM signal are adapted for reducing peak-to-RMS amplitude ratios of amplitude modulation signals in polar modulation transmitters. Peak-to-RMS amplitude ratio reduction is performed in the quadrature domain, the polar domain, or both the quadrature and polar domains.

Abstract: An apparatus for phase modulation includes a delay locked loop configured to generate from a reference signal a plurality of phase shifted signals, each of the phase shifted signals being locked to the reference signal and having a different phase shift from the other phase shifted signals with respect to the reference signal, and a multiplexer configured to select one of the phase shifted signals.

Abstract: A feedback loop is used to determine phase distortion created in a signal by directly extracting the phase distortion information from a feedback signal using original frequency modulation information.

Abstract: A device of dynamic communication of information allows, on the average, non-integer bits per symbol transmission, using a compact code set or a partial response decoding receiver. A stream of selectable predetermined integer bits, e.g., k or k+1 data bits, is grouped into a selectable integer number of bit vectors which then are mapped onto corresponding signal constellations forming transmission symbols. Two or more symbols can be grouped and further encoded, so that a symbol is spread across the two or more symbols being communicated. Sequence estimation using, for example, maximum likelihood techniques, as informed by noise estimates relative to the received signal. Each branch metric in computing the path metric of a considered sequence at the receiver is weighted by the inverse of the noise power. It is desirable that the constellation selection, sequence estimation and noise estimation be performed continuously and dynamically.

Abstract: A transmitter apparatus capable of reducing the distortions of vector modulated waves. This apparatus includes variable coefficient filters (110,112) in a stage preceding an amplitude signal voltage generating part (104) and also includes variable coefficient filters (111,113) in a stage preceding a phase modulated wave generating part (105). These variable coefficient filters (110-113) are used to perform a pulse shaping, thereby adjusting the delay between an amplitude component modulated signal (r(t)) and a phase component modulated signal (SC(t)) whereby a resolution, which is finer than the sampling period of a signal processing, can be used to adjust the delay time difference between the amplitude component modulated signal (r(t)) and the phase component modulated signal (SC(t)). As a result, the distortions of vector modulated waves (Srf(t)) can be reduced to a sufficiently small level.

Abstract: A communication apparatus used in a spectrum sharing environment in which multiple communication systems coexist using the same spectrum band is provided. The apparatus includes a transmission pulse shaper that performs bandwidth limitation on a pulse which is used to send data symbols; a monitoring unit that monitors in-band interference conditions from coexisting systems other than a target system to which the communication apparatus belongs, and availability of unused spectrum on adjacent channels of the target system; a controller that controls a pulse transmission period and a pulse width of the transmission pulse shaper based on the monitoring result; and a transmission unit that transmits the band-limited signal.

Abstract: A polar modulation transmission apparatus is disclosed, which reduces the circuit scale by removing isolators and which reduces the heat loss of a power amplifier. In this apparatus, current detecting section 130 detects current value Icc of current flowing from power supply voltage section 120 to power amplifier 180, and power control section 140 outputs control signal S31 to power apply section 150 based on power control signal S30 to be inputted and current value Icc. Power apply section 150 forms amplitude modulation signal S13 by multiplying baseband amplitude modulation signal S11 by control signal S31, and regulator 160 supplies to power amplifier 180 power supply voltage S22 converted into power supply voltage S21 by amplitude modulation signal S13. Power amplifier 180 obtains RF transmission signal S15 by amplifying the power of phase modulation high-frequency signal S14 as the power supply of power supply voltage S22.

Abstract: Some embodiments disclosed herein relate to a transmitter. The transmitter includes a digital modulator adapted to provide a digital modulated RF signal based on a multi-bit representation of data and a multi-bit representation of a carrier wave. A digital-to-analog converter (DAC) is adapted to generate an analog modulated RF signal based on the digital modulated RF signal. A resonant circuit coupled to an output of the DAC and adapted to filter undesired frequency components from the analog modulated RF signal.

Abstract: A method, apparatus, and computer program is presented for use in a radio transmitter using a polar transmitter structure in which a transmission signal is separated into an amplitude component and a phase component. The transmission signal includes transmission symbols distributed to a number of transmission resource blocks allocated to the radio transmitter for transmission. The amplitude component of the transmission signal is low-pass filtered in a low-pass filter configured by filtering parameters selected according to the number of transmission resource blocks allocated to the radio transmitter. Then, the low-pass filtered amplitude component is used in power supply of a power amplifier configured to power-amplify a phase component of the transmission signal.

Abstract: An input digital signal is periodically and alternately subjected to first modulation and second modulation, being thereby converted into a pair of a baseband I signal and a baseband Q signal. The first modulation and the second modulation are different from each other. The pair of the baseband I signal and the baseband Q signal are outputted. The first modulation may be at least 8-signal-point modulation while the second modulation may be phase shift keying.