Thomson-csf

Didier Kaminsky

Alain Bert

Gerard Kantorowicz

Narguise Mamodaly

Yves Archambault

A frequency-doubling voltage-controlled oscillator (VCO) for use in the microwave frequency range has two channels which operate in parallel. A transistor is mounted as an oscillating system in each channel and its energy is collected on the drain electrode. The two transistors are mounted with their output currents in opposite phase, thus reducing FM noise in the vicinity of the carrier. In accordance with the invention, phase opposition is obtained by means of a varactor connected between the gates of the two transistors. The varactor is decoupled in direct current by means of two capacitors. In order to increase the range of frequencies, two additional varactors can be mounted in like manner on the source circuits of the two transistors.

Frequency-doubling voltage-controlled oscillator

A frequency divide-by-two circuit capable of operating from substantially DC up to the maximum operating frequency of the component devices. First and second mixer stages receive the signal to be divided and its antiphase complement. The mixer output signals are amplified and summed. A portion of the sum signal is fed back to the other inputs of the mixers. The mixing amplifying and summing functions can all be performed by two FETs each having two gates. The divider can be integrated on a single chip since it does not make use of a filter. It can be used at frequencies of up to about 25 GHz.

Analog and aperiodic frequency divide-by-two circuit

The invention relates to a quadrupole for resistive matching of a reactance of the RLC type connected in series or in parallel, which permits to compensate for the loss of gain of an amplifier as the frequency rises, in a manner independent of the frequency. This quadrupole comprises two impedance circuits Z.sub.1 and Z.sub.2 in series between an input terminal and an output terminal, and in parallel with these, a third impedance circuit Z.sub.3. It also comprises a fourth impedance circuit Z.sub.4 connected between the point common to the first two circuits Z.sub.1, Z.sub.2 and the point common to the two other terminals of the quadrupole. The reactance which is to be matched is Z.sub.3 if it is of the RLC type connected in parallel. It is Z.sub.4 if it is of the RLC type connected in series. The values of the three other impedances Z.sub.1, Z.sub.2 and Z.sub.4 or Z.sub.3 are related so that the input impedance may be equal to the output impedance.

Quadrupole for matching of a reactance, independently of the operating

An ultra-high frequency oscillator having a very high thermal stability using a transistor coupled by a microstrip-type transmission line to a dielectric resonator with a very low temperature coefficient. It incorporates a field effect or bipolar transistor and an insulating substrate metallized or formed of metal on one face forming the ground plane. The latter projects over the substrate at a point close to two microstrip lines deposited on the face of the substrate opposite to the ground plane, the transistor being welded to said projecting point of the ground plane and to the microstrip lines. The assembly forms a compact hybrid circuit.

Ultra-high frequency oscillator with dielectric resonator of the compact

A device combining a certain number of elementary amplifiers formed on the same semiconductor wafer having a very high frequency (about 10 GHz), thus obtaining a monolithic amplifier with a high power and a wide pass band. This amplifier comprises at the input a first transmission line of the microstrip type, bent in such a way that it has an input branch and a tap branch where the waves reflected as a result of mismatches are absorbed in a resistive load. The bent region of line is connected to a row of elements of the impedance transformation lines passing to the gates (case of field effect transistors). It comprises at the output a second microstrip line parallel to the first and bias connected to a row of elements identical to those of the amplifier input.

Monolithic amplifier comprising a power division and recombination

The amplifier comprises two input and output transmission lines connected together by means of a plurality of active quadripoles mounted in parallel across the transmission lines, the elements for matching the quadripoles being inserted between the lines. In a solid state design, the active quadripoles are formed in a gallium arsenide substrate and the lines are constituted by metallic deposits formed on the substrate by means of the microstrip technique. The matching elements comprise inductance coils between which are placed coupling capacitors.

Distributed amplifier for microwave frequencies

A microwave oscillator in which the power supplied by 2N microwave diodes such as avalanche or Gunn effect diodes is added. The diodes are connected together in two by sections of strip lines which enables magnetic coupling between these diodes and a dielectric resonator, with the diodes in each couple operating in phase opposition.

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Paris, France

Didier Kaminsky