摘要:
A circuit arrangement and a method for obtaining a signal for use in downconverting a signal of a relatively high frequency VCO (7). A pulse train (S 1 ) is generated as a function of a reference signal which is then fed into an oscillator (2) so as to generate a signal (S 2 ) modulated by said pulse train (S 1 ). The resulting signal is fed into a band pass filter (4) which in turn outputs a selected frequency band (S 3 ) to be mixed with the signal of VCO (7) in order to obtain the down converted control signal for phase locking.
摘要:
The invention relates to a frequency generator which comprises a controlled oscillator (16) having a control input and an oscillator output. Said controlled oscillator (16) is adapted to output on the oscillator output an oscillator signal (Sout) having an oscillator frequency that depends on a control signal (SLOC) on the control input. The generator further comprises a scanning device (12) for scanning, by means of a reference frequency, the oscillator signal (Sout) or a signal of the controlled oscillator (16) that is derived from the same in order to obtain a scanned signal (Sd). A low-pass filter (14) is used to low-pass filter the scanned signal (Sd) or a signal derived from the same in order to obtain the control signal (SLOC) or a signal (STP) which is based on the control signal (SLOC). Due to its less complex design, especially the absence of a frequency divider, and the faster adjustability of the actually generated frequency, the inventive frequency generator allows to generate frequencies in an energy-saving manner.
摘要:
There is provided a voltage-controlled oscillator (5) whose oscillation frequency is controlled by a control voltage, a reference oscillator (1), and a sampling phase detector (3) for receiving an oscillation signal of the voltage-controlled oscillator and a reference oscillation signal of the reference oscillator and for inputting, to the voltage-controlled oscillator, as the control voltage, an error voltage that is obtained on the basis of a phase difference between the oscillation signal and a harmonic of the reference oscillation signal. An irreversible circuit element (6) is provided between the voltage-controlled oscillator and the sampling phase detector. The oscillation signal that is output from the voltage-controlled oscillator is input to the sampling phase detector via the irreversible circuit element.
摘要:
Der Erfindung liegt die Aufgabe zugrunde, eine rauscharme Sampling-PLL für hochauflösende Radarsysteme zu schaffen. Diese Aufgabe wird erfindungsgemäß dadurch gelöst, daß die Referenzfrequenzen einem Linienspektrum (SPK) entnommen sind, das durch Mischung einer niedrigen Quarzoszillatorfrequenz (F1) mit einer hohen Quarzoszillatorfrequenz (F2) erzeugt ist, wobei die Quarzoszillatorfrequenzen (F1,F2) synchronisiert sind. Die Erfindung findet Anwendung in Sampling-PLLs für hochauflösende Radarsysteme mit einem steuerbaren Frequenzoszillator dessen Ausgangssignal teilweise in einen Rückkopplungszweig ausgekoppelt und in einem Phasenvergleicher mit Referenzfrequenzen verglichen ist.
摘要:
A SAW stabilized oscillator (10) includes a phase locking circuit (38,16,20,22,36) which is phase locked to a lower frequency reference signal having an odd order difference with respect to the fundamental frequency of the SAW oscillator (14). A mixer (54) is disposed in the phase locking circuitry and is used as a sub-harmonic phase detector by mixing the fundamental (54a) with an odd harmonic (54b) of the reference signal (10a). The mixer output (54c) is filtered (70) and amplified (72,74) before being supplied to the control voltage input terminal (36′) of a voltage controlled variable phase shifter (36) in the SAW oscillator (14) loop (13).
摘要:
A frequency synthesized, microwave signal generator (50) is disclosed that provides multiple channel frequency selection capability with rapid channel change time and low levels of spurious signals and noise. The generator (50) uses a microwave harmonic phase locked loop (82) to lock a microwave VCO (68) to a programmable harmonic of a VHF reference crystal oscillator (60) to provide coarse frequency control in steps equal to that reference frequency. The phase lock loop (82) includes an offset mixer (74) for injecting an offset signal frequency to achieve fine frequency control. A harmonic detection and counting scheme is used to rapidly sweep the harmonic loop (82) and to obtain phase lock at the desired harmonic (Figure 1).
摘要:
L'invention concerne un générateur de fréquence pour un équipement radiofréquence pour générer un signal de sortie ayant une fréquence de sortie (F s ) prédéterminée, le générateur de fréquence comprenant : un oscillateur local (3) pour générer un signal de référence ayant une fréquence de référence (Fref), et une boucle à verrouillage de phase (5), la boucle à verrouillage de phase étant munie d'un oscillateur contrôlé (25) générant le signal de sortie ayant la fréquence de sortie (F s ) en fonction d'un signal à son entrée, et d'un comparateur (21) fournissant un signal à l'oscillateur contrôlé (25) en fonction d'une comparaison (C) de phase et/ou de fréquence d'un premier signal de comparaison (Fcomp1) basé sur un signal d'entrée appliqué à une première entrée (16) de la boucle à verrouillage de phase (5) avec un deuxième signal de comparaison (Fcomp2) basé sur le signal de sortie, le générateur de fréquence (1) comprenant en outre au moins un générateur d'harmonique (7) propre à générer, à partir du signal de référence, un signal d'harmonique comportant une harmonique prédéterminée (F H ) du signal de référence, le générateur de fréquence étant propre à appliquer le signal d'harmonique de l'un des générateurs d'harmonique à la première entrée (16) de la boucle à verrouillage de phase (5). En outre, la présente invention concerne un procédé pour générer un signal de sortie.
摘要:
There is provided a voltage-controlled oscillator (5) whose oscillation frequency is controlled by a control voltage, a reference oscillator (1), and a sampling phase detector (3) for receiving an oscillation signal of the voltage-controlled oscillator and a reference oscillation signal of the reference oscillator and for inputting, to the voltage-controlled oscillator, as the control voltage, an error voltage that is obtained on the basis of a phase difference between the oscillation signal and a harmonic of the reference oscillation signal. An irreversible circuit element (6) is provided between the voltage-controlled oscillator and the sampling phase detector. The oscillation signal that is output from the voltage-controlled oscillator is input to the sampling phase detector via the irreversible circuit element.
摘要:
A SAW stabilized oscillator (10) includes a phase locking circuit (38,16,20,22,36) which is phase locked to a lower frequency reference signal having an odd order difference with respect to the fundamental frequency of the SAW oscillator (14). A mixer (54) is disposed in the phase locking circuitry and is used as a sub-harmonic phase detector by mixing the fundamental (54a) with an odd harmonic (54b) of the reference signal (10a). The mixer output (54c) is filtered (70) and amplified (72,74) before being supplied to the control voltage input terminal (36′) of a voltage controlled variable phase shifter (36) in the SAW oscillator (14) loop (13).