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:
Die Vorrichtung dient zur gleichzeitigen Erfassung von zwei elektrischen Schwingungen mit unterschiedlichen Frequenzen. Es ist dazu ein Schwingquarz (1) mit mindestens zwei unterschiedlichen Resonanzfrequenzen vorgesehen. Ein Emitter eines ersten Transistors (2) ist über den Schwingquarz mit einem Emitter eines zweiten Transistors (9) verbunden. Die Basen der Transistoren sind jeweils über Basisschwingkreise (11,17) mit einem unteren Bezugspotential und die Kollektoren der Transistoren jeweils über Kollektorschwingkreise (5,14) mit einem oberen Bezugspotential verbunden. Die Basis jeweils eines der Transistoren ist elektrisch mit dem Kollektor jeweils des anderen Transistors verbunden. Die Basen der Transistoren sind jeweils über Wechselstromkoppler an das untere Bezugspotential angeschlossen.
摘要:
A frequency generator produces two widely spaced frequency outputs at the terminals of a single transistor. There is also disclosed a fixed frequency dual downconversion receiver, comprising: an analog first downconversion and IF filter stage; means for one-bit coding of the downconverted signal; and means for second downconversion by digital subsampling. The receiver is particularly suitable for use in GPS appliocations, and the frequency generator can advantageously be used to produce the local oscillator signal for the first mixer, and a clock signal for the digital subsampler.
摘要:
The invention pertains to a push-push oscillator circuit (10) with a first oscillation branch with a first active device (12) and a first tank (16, 20) adapted to provide a signal having a fundamental frequency f 0 , a second oscillation branch with a second active device (14) and a second tank (18, 22) symmetrical to the first oscillation branch and adapted to provide a signal having the fundamental frequency f 0 . Output branches (24, 28, 50, 60) are coupled to the first oscillation branch and the second oscillation branch to provide signals having the second harmonic frequency 2f0 of the fundamental signal based on the signals having the fundamental frequency f 0 and/or to provide signals having the fundamental frequency f 0 . The push-push oscillator circuit (10) further comprises at least one terminal branch (36, 58, 68, 78) with a terminal (42, 82, 94, 100) adapted to provide a component of a differential signal having the second harmonic frequency 2f0 or the fundamental frequency f 0 . The at least one terminal branch (36, 58, 68, 78) comprises a RF stub (44, 84) comprising a quarter-wavelength transmission line (46, 86, 102, 106) and a corresponding capacitor (48, 88, 104, 108) for a signal having the second harmonic frequency 2f 0 or the fundamental frequency f 0 . The invention also pertains to a push-push oscillator circuit (10) having output branches (24, 28, 50, 60) coupled to the first oscillation branch and the second oscillation branch to provide signals having the fundamental frequency f 0 . One of the output branches (50) comprises two coupling inductors (52, 54) and a first fundamental frequency branch (58) having a first fundamental frequency terminal (94), the first fundamental frequency branch (58) being coupled in series with one of the coupling inductors (54), the two coupling inductors being coupled to each other in series via a first connection point. Another one of the output branches (60) comprises two coupling inductors (62, 64) and a second fundamental frequency branch (68) with a second fundamental frequency terminal (100), the second fundamental frequency branch (68) being coupled in series to one of the coupling inductors (54) of this output branch (6), and the two coupling inductors (62, 64) of this output branch (60) being coupled to each other in series via a second connection point. The push-push-oscillator circuit (10) is adapted to provide a differential signal having the fundamental frequency f 0 at the first and second fundamental frequency terminals.
摘要:
A frequency-generator circuit employs the same circuit element (preferably a varactor) to perform the functions of parametric frequency-divider and frequency-adjustment element for an oscillator used to pump the parametric frequency-divider.The varactor preferably has a flat gamma-characteristic (gamma preferably > 2) over a required bias-voltage adjustment range corresponding to the required frequency-adjustment range.
摘要:
A fixed frequency dual downconversion receiver, comprises: an analog first downconversion and IF filter stage; means for one-bit coding of the downconverted signal; and means for second downconversion by digital subsampling. The receiver is particularly suitable for use in GPS applications.
摘要:
Die Erfindung betrifft eine Schaltungsanordnung zum Erzeugen eines niederfrequenten Wechselstroms, wie er besonders für Elektromassagen verwendet wird. Durch Zusammenschalten mehrerer Generatoren mit unterschiedlichen, einstellbaren Grundfrequenzen und eine Einstellbarkeit von Koppelgliedern können beliebige Frequenzgänge und Schwebungen erzeugt werden, die sich als besonders wirksam erwiesen haben. Vor allem wird die für den menschlichen Körper gefährliche Komponente der Netzfrequenzen von 50-60 Hz vermieden.
摘要:
Oscillateur (100) multi-mode comportant : - un résonateur (10) comprenant : • un élément mobile (12) ; • des moyens d'actionnement (18, 20) de l'élément mobile selon deux modes de résonance symétrique et antisymétrique ; • plusieurs éléments de détection (22, 24, 26, 28) du déplacement de l'élément mobile ;
- des moyens de polarisation (101) des éléments de détection par des signaux déphasés l'un par rapport à l'autre ; - un premier dispositif de calcul (102) réalisant une première opération conservant les composantes fréquentielles du premier mode et annulant celles du deuxième mode ; - un deuxième dispositif de calcul (108) réalisant une deuxième opération conservant les composantes fréquentielles du deuxième mode et annulant celles du premier mode ; et dans lequel le résonateur et les dispositifs de calcul forment deux boucles auto-oscillantes mettant simultanément en résonance l'oscillateur dans les deux modes.