摘要:
This application relates to an apparatus comprising a signal generator configured to generate a signal. The apparatus encompasses a predistortion unit configured to pre-distort the generated signal. The apparatus includes a pulse width modulating unit configured to modulate the pre-distorted signal into at least two signals. The apparatus comprises at least two amplifying units each configured to amplify one of the two modulated signals.
摘要:
A baseband signal generator (102a) provides a polar signal (A, I p) to a processing sub-unit (704p). The processing sub-unit (704p) receives furthermore feedback signals from a down converting unit (704c) which feedback signals are used to determine the magnitude (B) of the amplified output signal and the actual error phase. The magnitude (A) of the polar signal and the determined magnitude (B) are applied to a comparator (710) having its output connected to the input of a predistortion unit (214, 216). The output of the predistortion unit (214, 216) is connected to the input of a pulse width modulating unit (210, 212) which comprises a mapping unit (210) outputting two constant magnitude signals. The actual error phase and the phase component of the polar signal are used to generate a corrected phase component which is applied to a further mapping unit (202) forming part of a phase modulating unit (202, 204). The output signals of this phase modulating unit (202, 204) are applied to the pulse width modulating unit (210, 212) providing finally two pulse width pulse position modulated signals. These signals are applied to the switching amplifier (110).
摘要:
The application refers to an apparatus comprising, a signal generator (102, 102a) configured to generate a signal, a first pulse width modulating unit (106) configured to modulate the signal, an amplifier unit (110) configured to amplify the modulated signal, a feedback loop path (108a) configured to correct the modulated signal using an error signal, wherein the apparatus comprises a second pulse width modulating (108) unit configured to modulate the error signal onto the modulated signal.
摘要:
An apparatus comprising a signal generator for generating a polar representation of a signal. The apparatus comprises further a first filtering unit configured to filter a low frequency part of the amplitude component of said signal and a second filtering unit configured to filter a high frequency-part of the amplitude component of said signal. In addition, the apparatus includes a pulse width modulating unit configured to modulate the filtered high frequency part of the amplitude component of said signal together with the phase component of said signal. Finally the apparatus includes a DC-DC converter configured to convert the filtered low frequency part of the amplitude component of said signal. Said DC-DC converter supplies a switching mode power amplifier for amplifying the pulse width modulated signal.
摘要:
The application relates to a digital modulator comprising at least one input terminal configured to receive at least one signal, at least one symbol generating unit comprising a first output terminal and at least a second output terminal, wherein the symbol generating unit is configured to generate a first symbol waveform for the first output terminal depending on the received signal, and wherein the symbol generating unit is configured to generate at least a second symbol waveform for the second output terminal depending on the received signal, wherein the first symbol waveform comprises at least one different parameter value compared to the second symbol waveform, at least one third output terminal connectable to at least the first output terminal and/or second output terminal via a switching unit, a controlling unit configured to control the switching unit depending on the received signal such that a modulated output signal is generated.
摘要:
The present invention relates to a circuit arrangement and method of applying predistortion to a baseband signal used for modulating a pulse-shaped signal, wherein an envelope information of the baseband signal is detected and slewing distortions of the pulse-shaped signal are reduced by applying at least one of a phase modulation and a duty cycle 5 modulation to the baseband signal as additional predistortion in response to the detected envelope information. Thereby, slewing distortions in the pulse-shaped signal are removed or at least reduced.
摘要:
This application relates to an apparatus comprising a signal generator configured to generate a signal. The apparatus encompasses a predistortion unit configured to pre-distort the generated signal. The apparatus includes a pulse width modulating unit configured to modulate the pre-distorted signal into at least two signals. The apparatus comprises at least two amplifying units each configured to amplify one of the two modulated signals.
摘要:
The application refers to an apparatus comprising, a signal generator (102, 102a) configured to generate a signal, a first pulse width modulating unit (106) configured to modulate the signal, an amplifier unit (110) configured to amplify the modulated signal, a feedback loop path (108a) configured to correct the modulated signal using an error signal, wherein the apparatus comprises a second pulse width modulating (108) unit configured to modulate the error signal onto the modulated signal.
摘要:
The present invention relates to a circuit arrangement and method of applying predistortion to a baseband signal used for modulating a pulse-shaped signal, wherein an envelope information of the baseband signal is detected and slewing distortions of the pulse-shaped signal are reduced by applying at least one of a phase modulation and a duty cycle 5 modulation to the baseband signal as additional predistortion in response to the detected envelope information. Thereby, slewing distortions in the pulse-shaped signal are removed or at least reduced.
摘要:
A quadrature out-phasing system comprising: a first baseband signal modifier (6) arranged to receive a first baseband signal component (2) and output a first constant envelope RF carrier (12) and a second constant envelope RF carrier (14); and a second baseband signal modifier (8) arranged to receive a second baseband signal component (4) and output a third constant envelope RF carrier (16) and a fourth constant envelope RF carrier (18). The system may further comprise: a first signal combiner (500) arranged to combine the first constant envelope RF carrier (12) and the second constant envelope RF carrier (14), and arranged to output a first RF PWM signal (94); and a second signal combiner (502) arranged to combine the third constant envelope RF carrier (16) and the fourth constant envelope RF carrier (18), and arranged to output a second RF PWM signal (96).