Abstract:
A planar balun coupled frequency translator (upconverter or downconverter, is illustrated in various configurations for providing both full-wave and half-wave signal frequency conversion. As illustrated, each of the circuits uses microstrip and strip transmission line construction techniques for cost effective construction. As designed, the carrier and signal frequency baluns are separately interfaced in sets rather than all being connected in series as in the prior art.
Abstract:
A unitary component operating as a low noise amplifier incorporates several other tuning components in conjunction with an FET. By adjusting the tuning components, the overall amplification and impedance characteristics of the unit can be standardized in spite of typical variations in impedance and amplifying characteristics of the FET by itself. The incorporation of such a drop-in module in a microwave circuit, simplifies testing and repair of the remaining portions of the circuit, since the drop-in modules can easily be tested and adjusted for proper operation in a test jig separate from the actual operating circuit.
Abstract:
Microwave circuit layout structure is disclosed for a diode quad mixer frequency converter with separate, isolated sections, each supplied by a respective half of dual balun port structure. The circuit layout structure is compact and symmetric, and enables coplanar diode connection.
Abstract:
A balun coupled microwave frequency converter is provided by a mixer using a single diode pair with one port balanced and the other port unbalanced. The balanced port is provided by first and second coplanar conductors extending toward a common area and juxtaposed in spaced parallel relation with a transmission line interacting therewith to couple a field balanced between the first and second conductors across the common area. The unbalanced port to the mixer is provided by a third conductor. The diode pair is connected in series between the first and second conductors, and a point between the diodes is connected to the third conductor. One implementation is an up converter with an LO and an IF signal applied on the third conductor and input to the mixer to generate an RF signal between the first and second conductors and hence an induced output RF signal on the transmission line.
Abstract:
The present invention uses two interconnected baluns with the balanced output of one feeding a balanced input of the other. When this filter is used in conjunction with a signal frequency converter, the balun pair not only provides extremely effective bandpass filtering so as to pass the RF frequencies and not the IF frequencies but, in addition, provides a condition which appears to the IF as a nearly open circuit and thus provides a large amount of reflection or return of the IF signals to the signal converter. Through the use of additional grounding stubs, additional coupling means, increased separation between coupling means and separated ground planes each singularly or in combination, improved performance has been obtained as compared to the prior art.
Abstract:
A variable transformer is illustrated to be used primarily with high frequency transistors and other high frequency amplifying means to provide optimum impedance matching characteristics for individual transistors in a circuit rather than trying to design a given circuit to be universally applicable to a range of transistor characteristic values.
Abstract:
Microwave circuit layout structure is disclosed for a diode mixer bridge. The circuit layout structure is compact and symmetric, and enables short orthogonal equal length leads from a diode ring quad mixer bridge. The configuration also affords equal path lengths through the diodes to provide precise 180.degree. phase differential image frequency cancellation. The structure also affords precise and consistent mounting of the mixer bridge, to further improve performance.
Abstract:
A microwave frequency converter is provided with a diode mixer bridge having a balanced port connected to a dual balun. The dual balun is provided by two pairs of balanced secondary conductors juxtaposed a common primary conductor, each pair contributing to the field between balanced conductors leading to the mixer bridge. The dual balun and microstrip circuit layout enable a wider gap to be used between the balanced conductors to the bridge, which enables manufacturably cost efficient implementation.
Abstract:
A microwave frequency converter is provided with cost effectively manufacturable microstrip layout circuitry, particularly for directionally coupling the LO signal. A pair of unbalanced microstrip conductors lead from a mixer bridge respectively to a pair of balun IF rejection filters juxtaposed on the opposite side of a dielectric substrate. A second pair of unbalanced microstrip conductors lead respectively from the pair of balun IF rejection filters to a microstrip branch line coupler.
Abstract:
A low frequency, diode pair mixer is provided in combination with simple, compact transformer circuitry. A diode mixer bridge has a pair of diodes interconnecting secondary windings of single and dual transformers. The diodes are connected in series across the secondary winding of the single transformer. The same polarity ends of the pair of secondary windings of the dual transformer are connected in common to a point between the diodes. The other ends of the pair of secondary windings are connected to respective ends of the secondary winding of the single transformer. The combination affords isolation between the signals coupled through each of the transformers. The combination may be implemented as an up converter or a down converter.