| 摘要 |
926,598. High-frequency amplifiers. TELEFUNKEN PATENTVERWERTUNGS G.m.b.H. Nov. 21, 1961 [Nov. 22, 1960], No. 41643/61. Class 40 (9). [Also in Group XL (c)] A non-reciprocal circuit arrangement includes at least an up-converter in series with a downconverter, both operating with the same heterodyne frequency, the active element of one converter M1 being a non-linear susceptance B, and the active element of the other M2 being a non-linear seal conductance W. Non-linear susceptance B may be a capacitance diode, a non-linear inductance or a pre-magnetized ferrite element; and the non-linear conductance W may be a conventional diode or a tunnel diode. If a tunnel diode is used a transmission gain greater than unity is possible. The input may be isolated from the output, and the reverse transmission of the frequency-changer chain neutralized, by providing a passive, linear and reciprocal coupler K between the input and output terminals. Depending on whether the pumping frequency is applied to the frequency changers in the same or opposite (using phase shifter Ph) phase, and on whether the upconverter precedes or follows the down-converter, this may be an inductance or a capacitance. An additional frequency-changer, e.g. a self-oscillating grounded-grid mixer, may be connected to the output terminal to give an overall frequency change. The local oscillator O is preferably gang-controlled with the signal frequency fs so that the intermediate frequency, between M1 and M2, remains constant. |
