RU2610387C1 - Capacitive double-resonance array for frequency usb - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: third conductive surface forming with a grounded conductive surface of the capacitive element the second capacitive element, an inductor connected to the third conductive surface and a matching device, two pins of which are connected to the second outlets of inductors are added, one outlet is grounded, and the input is connected to the feeder line center conductor.

EFFECT: expansion of the capacitive array functionality by double-resonance system constructing.

2 cl, 2 dwg

Description

The invention relates to antenna technology and can be used to create transceiver antenna devices for portable radio communication equipment of the VHF frequency range.

As a prototype, a capacitive antenna was selected (Patent RU No. 2470424) containing a capacitive element deployed in space, the plates of which are made in the form of two cylindrical conductive surfaces, an inductor and a matching inductor. Such an antenna in the VHF frequency range has a narrow working band and can only work on one structurally set frequency (it has one resonance).

The aim of the invention is to expand the functionality of a capacitive antenna by constructing a two-resonance system.

The technical result is achieved by the fact that:

- in order to expand the functionality of a capacitive antenna, a second inductor and a second capacitive element in which one of the conductive surfaces is common to both capacitive elements are additionally included in its design;

- in order to reduce the negative influence of spurious connections and simplify the overall layout of the antenna, the conductive surfaces (plates) of capacitive elements are made flat and are located so that the common panel is in the middle between the other two and is grounded.

The drawing shows:

FIG. 1 is a circuit diagram of a capacitive two-resonance antenna for the VHF frequency range, where the numbers indicate:

1.1, 1.2, 1.3 - flat plates of capacitive elements;

2.1, 2.2 - inductance coils of antenna loops;

3 - matching device.

FIG. 2 - frequency response of the standing wave coefficient.

A two-resonance capacitive antenna for the VHF frequency range contains two capacitive elements deployed in space, formed by three flat plates, one of which is common. The plates are located in the same plane and in one row so that the common for both capacitive elements lining is in the middle and is grounded. Inductors 2.1 and 2.2 are connected to the plates 1.1 and 1.3 of the capacitive elements. In this case, a system is formed of two coupled oscillatory circuits (antenna circuits) tuned to two different resonant frequencies of the emitted (received) electromagnetic signal.

In FIG. 2 shows a screenshot of a vector network analyzer, which depicts a two-resonant frequency response of such a capacitive antenna. In this case, the characteristic has resonances at the frequencies of 148.3 MHz and 170.9 MHz, which are the operating frequencies of the antenna and are set during the initial tuning of the antenna.

The feeder line is connected to the antenna through a matching device, each of the two outputs of which are electrically matched with the corresponding antenna circuit. The standing wave coefficient (see Fig. 2) at the working frequencies is 1.1 and 1.04, respectively, which indicates a high degree of matching of the antenna and the feeder line having a wave impedance of 50 Ohms.

When emitting along one feeder line from the transmitter, a signal voltage of one or another high frequency is applied. Resonance occurs in that circuit, the tuning frequency of which coincides with the frequency of the input signal. In this case, between the plates of its capacitive element deployed in space, an alternating voltage of high frequency arises, Q times the input voltage (Q is the quality factor of the antenna circuit). The high-frequency electric field acting between the plates induces bias currents in the surrounding space, due to which high-frequency electromagnetic radiation (electromagnetic wave) occurs.

Thus, the configuration of the capacitive antenna under consideration (Fig. 1) allows its use at two fixed frequencies without tuning the antenna circuit, which extends the functionality of the antenna.

Claims (2)

1. Two-resonance capacitive antenna for the VHF frequency range, containing a capacitive element deployed in space in the form of two conductive surfaces and an inductor connected in series with one of them, and the other conductive surface is grounded, characterized in that a third conductive surface is added, forming with the grounded conductive surface of the capacitive element, the second capacitive element, an inductor connected to the third conductive surface, and a measuring device, two terminals of which are connected to the second terminals of the inductors, one terminal is grounded, and the input is connected to the central conductor of the feeder line. 2. A two-resonance capacitive antenna for the VHF frequency range according to claim 1, characterized in that the conductive surfaces of the capacitive elements are flat and arranged in a row in the same plane, and the common conductive surface is located between two others, grounded, and connected to the outer braid of the feeder line.

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