CS267063B1 - Connection of six-outlet reflecto-meter - Google Patents

Abstract

The solution belongs to the microwave area techniques and solves a simple type of configuration six-port reflectometer for measurement coefficient of reflection ró. The essence of the solution is that switching in the reflective phase an angle of rotation is obtained by the slider three q-points of the six-port reflectometer, wherein only two detectors are used in the circuit and its configuration. is broadband. This effect is achieved by having the generator is connected to the first power divider, on which is connected to the first detector and the second divider performance. Reflective phase is connected to it a slider and a third power divider to which it is connected second detector and terminal for connection measured load.

Description

The invention relates to the connection of a six-port reflectometer, which serves to measure the reflection coefficient S of the connected load.

The basis of the six-port reflectometer is a linear six-port. The state of the six port is determined by twelve variables, which can be incoming and outgoing waves with amplitudes a ^ and b ^, where i takes values from 1 to 6.

. On the measuring port on which the unknown load is measured, the waves are marked as follows:

a ₆ = ab, = b O

The following applies to the reflectometer outputs:

^P i ⁼ | ^A i ^{a + B} i ^b | ^{2 <: i} · ^{= 2} ' ³ ' ⁴⁾

P. = | _A J ² | b | ² q. | ² (i = 1, 2, 3, 4) where ξ = g is the reflection coefficient of the measured load a

B, '

Cf ^ = - are the so-called q-points of the reflectometer.

Several types of six-port reflectometer configurations are currently known. According to Samuel and Li Bosisia, a six-port reflectometer with probes is known, whose port 4 samples the wave b and ports 1 to 3 have projecting waves b ^ = C | b (? + E ^ ^2ei ), where the probe binding coefficient and the electrical distance of the probe from measuring plane. For the distance of the probes, the q-points lie on the unit circle.

A six-port reflectometer with directional taps with a short-circuited arm is also known. For the wave emanating from the second port (i = 1, 2, 3) b _± = cb (? - e ² ^ ®! - ^) where c ^ is the coefficient vMzby of the respective branch, is the electrical distance of the branch from the directional plane and CT = 2 ^^ is the electrical distance of the short circuit from the tap, d ^ being half of the distance which the wave must travel in addition to the fault b in order to reach the i-th detector. The position of the q-points can be set by the position of the shorts. The authors are Potter and

Snowden.

Six-port reflectometers with hybrids, power dividers and directional taps are also known. One of the various variations of configurations proposed by Engen, it has four directional taps with a 3 dB link and one directional tap with a 6 dB link. A similar reflectometer was constructed by Griffin, it has all directional taps with a vBzbu of 3 dB.

The six-port reflectometer with a symmetrically matched pportport, constructed by Riblet and Hanson, contains one directional tap responding only to the incident wave and a symmetrically matched pSport. The advantage of this configuration is the simple construction and the ideal distribution of q-points.

A six-port reflector with bound lines, designed by Collier and Nabil-El-Deeb, is also known. Its advantage is a simple configuration, but the disadvantage is the non-ideal distribution of q-points.

CS 267 063 Bl

A six-port reflectometer realized as a measuring three-port is also known. Its advantage is one detector, with which all powers are measured. The disadvantage is the need for a precise attenuator and amplitude modulator.

A common disadvantage of the currently used configurations of six-port reflectometers is, above all, their complex configuration, or in most cases the use of four detectors, or the narrowband of their use.

These shortcomings are substantially eliminated by the connection of a six-port reflectometer, consisting of a generator, two detectors and a terminal for connecting a measured load according to the invention, the essence of which is that the generator is connected to a first power divider to which the first detector is connected. The first power divider is connected to a second power divider, to which a reflective phase shifter is connected, and a third power divider, to which a second detector and a terminal for connecting the measured load are connected.

The advantages of the connection according to the invention lie! in that the number of detectors required is reduced to two of the usual four, thereby increasing measurement accuracy and eliminating the disadvantage of narrowband configuration with a dual directional tap using three power dividers. In addition, the configuration has an optimal q-point distribution, is very simple and allows to achieve an optimal angular displacement between 120 ° and -120 ° q-points.

In the accompanying drawing in FIG. 1 is a block diagram of a six-port reflectometer according to the invention, and FIG. 2 shows the optimal distribution of q-points.

The circuit according to the invention, as shown in FIG. 1, consists of a generator 5 connected to a first power divider 2, ^to which a first detector 2 and a second power divider 4 are connected. A reflex phase shifter T and a third power divider 2 to which the second detector 2 and terminal it for connecting the measured load. The first to third power dividers 2> Ir 8 have power vSzby Cp c ₂ , c _3>

The actual operation of the six-port reflectometer according to the invention is as follows. The signal from the generator J1 passes through the first and second power dividers 2 'A> Where it branches into two parts. The first part of the signal is reflected with the reflection coefficient = = r ^ e-) ¹ ^ - after impact on the reflective phase shifter 2, the amplitude of the reflection coefficient being close to one and the phase indicating the angular distribution of q-points, and after passing through the second and first power divider 4 ^ 2 impinges on the first detector 2 · The second part of the signal passes through the third power divider Where it is divided into two parts, while part of the signal impinges on the second detector 2, which responds only to wave b impinging on the load and part of the signal impinges on the measured the load connected to the terminal 2 P for ^the connection of the measured load is reflected from it and after passing through the third, second and first power divider 2 »A '2 it hits the first detector 2» where it adds the first part of the signal reflected from the reflex phase 7. The electrical path of the signal between the directional tap and the reference plane in which the reflection coefficient of the measured load is measured is © ₃ and © ₂ is the electrical path between the directional tap and the reflex phase shifter 2. · The effort is to hunted. In this case, the q-point system as a whole will not rotate when the frequency changes. The reflective phase shifter 2 can be implemented as a sliding short circuit, but, for example, an electronically controlled broadband reflective shifter can be advantageous. The relation applies to the q-points of the system

q. = r. - ~. _e 2 j (®2-®l> e ^ i ^{1 1} (A ^) ² wherein the binding power of the third power divider _8 the arm, which is measured by the load. The fall of 1 for ^j symmetrical separation performance, i.e., if ^a = 2 l ^e b ° = 3 dB in the third power divider will be q ^ = 2. A suitable reflective phase shifter 7 can achieve an ideal angular distribution of q-points, in which the q-points are shifted by 120 ° relative to each other.

Claims (1)

Connection of a six-port reflectometer, consisting of a generator, two detectors and a terminal for connecting the measured load, characterized in that the generator (5) is connected to a first power divider (3) to which the first detector (1) and the second power divider ( 4), to which a reflective phase shifter (7) and a third power divider (8) are connected, to which a second detector (2) and a terminal (6) for connecting the measured load are connected.