SU1298854A1 - Power amplifier - Google Patents

Abstract

The invention relates to radio engineering. The purpose of the invention is to increase efficiency. The amplifier contains active elements (E) 1 and 2, segments 3 and 4 of the transmission line and capacitive E connections 5 and 6. When capacitive E connection 5 is connected to a point at a distance K (where h is the signal wavelength) from the reclosed end of segment 3, and the capacitive E connection 6 to a point at a distance D / 6 from the short-circuited end of segment 4 receive the shape of the resulting voltage, close to the rectangular. In this form of voltage, the power dissipated in the active E 2 will be less than in the case of harmonic voltage, which increases the efficiency of the power amplifier. 3 il. with S (L s: Fig. 1

Description

The invention relates to radio engineering and can be used in radio transmitting devices.

The purpose of the invention is to increase efficiency

FIG. 1 is a circuit diagram of a power amplifier; in fig. 2 - dependence of the amplitudes of the voltages of the first (and,) and third (U,) signal harmonics as a function of distance (X) from the short-circuited end of the first segment of the transmission line; in fig. 3 - the same, as a function of the distance from the short-circuited end of the second segment of the transmission line.

The power amplifier contains the first 1 and second 2 active elements, the first 3 and second 4 segments of the transmission line, the first 5 and second 6 capacitive elements of the communication.

The power amplifier works as follows.

When a signal is applied to the input of the power amplifier, current pulses flow through the first active element 1 and contain common-mode oscillations of the first and third harmonics of the signal. As can be seen from FIG. 2, at a distance L / 12 from the short-circuited end of the pepper segment 3 of the transmission line, the third harmonic voltage is maximum and opposite to the voltage of the first harmonic. The first capacitive coupling element 5 is connected to this point. At the output of the second active element 2, the voltage also contains the sum of the voltages of the first and third harmonics, therefore, the shape of the resulting voltage is close to rectangular. With this form of voltage, the power-: The dissipation on the second active element 2 is less than in the case of harmonic voltage, therefore, K1SC power amplifier rises.

To simultaneously adjust the first 3 and second 4 segments of the transmission line to the first and third harmonics of the amplified signal, it is necessary to fulfill the condition

3arctg

t

coCoZo

.

arctg

one

To fulfill this condition with an accuracy of, for example, no worse than 2.

one

enough to take 2

Claims (1)

Invention Formula A power amplifier containing the first and second active elements, to one terminal of which the first and second sections of the transmission line are connected, short-circuited at one end, the other terminal of the first active element being the input of the power amplifier, another terminal of the second active element the capacitive communication element is connected to the first segment of the transmission line, and the power amplifier is connected to the second segment of the transmission line by its output via the second capacitive communication element, characterized in that When the efficiency rises, the first capacitive coupling element is connected to the first segment of the transmission line at a distance of A / 12 from its short-circuited terminal. and the second capacitive coupling element is connected to the second segment of the transmission line at a distance from its short-circuited end, where A is the wavelength of the signal. 2 Editor V. Netrash Compiled by Y. Danich Tehred N.Glushchenko Proofreader S.Shekmar 895/56 Circulation 902 Subscription VNII11I USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, st. Project, 4 Fig.Z