JPS6011843B2 - variable microwave generator - Google Patents

Description

[Detailed description of the invention] The present invention is a variable microphone.

It relates to a wave generator. Generally, the transmission frequency used in microwave communication systems is fixed. However, recently,
There is a growing demand for making the transmission frequency variable within a specified frequency band, and there is a desire for a variable microwave generator capable of meeting this demand. It is possible to realize such a variable microwave generator using a known continuously variable microwave oscillator. However, there are hardware problems regarding noise and the like, which is inconvenient when trying to obtain high quality microwaves in a continuously variable manner. For this reason, instead of a continuously variable type microwave generator, it is practical to use a variable type microwave generator that prepares multiple types of fixed microwave oscillators that do not have any problems with noise and switches between them to obtain the desired microwave. It is. However, as will be explained in detail later, the conventional variable microwave generator has disadvantages such as being large, expensive, and having a transmission loss, and few have been widely put into practical use. Therefore, an object of the present invention is to provide a variable microwave generator which eliminates the above-mentioned drawbacks and is suitable for practical use.

In accordance with the above-mentioned object, the present invention has a plurality of types of microwave oscillators installed in parallel via corresponding T-branches on a single transmission line equipped with a microwave output point and a reflection point at both ends. The present invention is characterized in that a microwave switch for selectively selecting the microwave oscillator is disposed at each T branch.

The present invention will be explained below with reference to the drawings.

FIG. 1 is a block diagram showing a first example of a general variable microwave generator.

In this figure, 11-1, 11-2...11-
n is a microwave oscillator with frequencies f, f2, . . . fn, respectively. Band pass filters 12-1, 12-2...12-n corresponding to frequencies f, f2...fn are connected to each microwave oscillator, and Circulator 13-1,1
3-2...connected to 13-n. Here, if the frequency fn is obtained as the microwave output rout, the switches 14-1 and 14 provided in each microwave oscillator
-2... Among the 14-n, only the switches 14-n are turned on, and the microwave oscillators 11-n are connected to the high source voltage V
The oscillation output is sent to the circulator 13-n.
→13-2→13-1 via microwave output Buddha ou
It becomes t. In this case, the microwave output of frequency fn is
Band passing filters 12-2, 12-1 of frequencies et, f,
The variable microwave generator shown in this figure, which once enters the direction of the microwave, is reflected and turned back, has the disadvantage that it has many parts such as a circulator and an Obishiro pass filter, and is large and expensive. FIG. 2 is a block diagram showing a second example of a general variable microwave generator.

In this figure, the same reference numbers or symbols used in FIG. 1 indicate the same components. In this second example, the designated microwave output of 1 is taken out as the muo mountain via the hybrid circuits 21, 22, 23, . . . . Therefore, it has the disadvantage that the device becomes large in size, and also has the fatal defect of large passing loss because the path to the output end is long. Therefore, we propose a variable microwave generator as shown in FIG.

FIG. 3 is a block diagram of a first embodiment according to the present invention,
Components labeled with the same reference numbers or symbols as in FIGS. 1 and 2 are the same components. As shown in this figure, according to the present invention, one transmission line 31 is first provided, and each microwave oscillator 1 is connected to the nuclear transmission line 31.
1-1, 11-2...11-n are each T branch road 3
2-1, 32-2, 32-3, 32-4, .
, 33-2, 33-3, 33-4...33-n are arranged. The microwave switches 33-1 to 33-n are turned on and off by a bias supply circuit and switches 34-1 and 34-3.
4-2, 34-3, 34-4...34-n are controlled by turning them on and off. Therefore, this bias supply circuit is
DC power supply Vdc, these switches, and pongee wires 35-1, 35-2, 35-3, 35-4...35 including LL components
-n. Now, suppose that it is desired to obtain a microwave output output of frequency f4, the switch 14-4 is turned on and the microwave oscillator 11-4 is driven. At the same time, the switch 34-4 linked to the switch 14-4 is turned on, and only the microwave switch 33-4 is turned on. Here, each microwave switch is directly connected to the transmission line 31, and the microwave output 04) from the microwave switches 33-4 that are turned on propagates toward both ends of the transmission line 31. Of these, reflection point 3
The microwaves directed towards 7 are turned back here and follow the microwaves that have already been sent directly to output point 36 . At this time, it is desirable that the distances from each T-branch point to the reflection point 37 have a certain relationship since they should be tracked in the same phase. That is, the microwave oscillator 11-1(f,)
If the distance from each T branch point connected to each of ~11-n(fn) to the reflection point 37 is L,, -, L3, L4...Ln, firstly, when the reflection point 37 is open, L = Uikari. ,}=sheep XN2, -=science×N3, L=alsoxN4...
...Set Ln=GakuXNn.

However, N,, N2...Nn are each unique natural numbers. Also ^・, ^2. ...^n is also the frequency mentioned above. f
2...The wavelength is determined by fn. Second, if the reflection point 37 is short, L = child, - = sheep leg 11)'
- = Gaku x leg 11)' L = Hour X (Shu 311) Skin Ln: Gaku X (Shu n 11) Set.

Thus, by turning on a desired microwave switch, a desired microwave output can be obtained. FIG. 4 is a block diagram showing a second embodiment based on the present invention.

The principle is the same as the first embodiment. However, the arrangement position of the microwave switch is different from that of the first embodiment.
While the microwave switch of the first embodiment opens or shorts each T branch path 32-1 to 32-1n, the second embodiment grounds each branch point or Depending on whether it is removed from the potential, the switch can function as an off or on function. As clarified by the first and second embodiments above, according to the present invention, it is small and
A variable microwave generator that is inexpensive and has extremely low transmission loss is realized.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a first example of a general variable microwave generator, Fig. 2 is a block diagram showing a second example of a general variable microwave generator, and Fig. 3 is based on the present invention. FIG. 4 is a block diagram showing a first embodiment of a variable microwave generator, and FIG. 4 is a block diagram showing a second embodiment of a variable microwave generator according to the present invention. In the figure, 11-1 to 11-n are microwave oscillators, 14-1 to 14-n, 34-1 to 34-n are switches, 31 is a transmission line, 33-1 to 33-n
are respectively microwave switches. Figure 1 Figure 2 Traditional Figure 3 Traditional map

Claims (1)

[Claims] 1. A transmission line having a microwave output point and a reflection point at both ends, and a plurality of types of microwave oscillators are arranged in parallel on the transmission line via corresponding T-branches. A variable microwave generator characterized in that a microwave switch for selecting an output from one of the microwave oscillators is provided for each of the T-branches. 2. If the wavelength of the output of any microwave oscillator is λ, and the distance between the corresponding branch point and the reflection point is L, then when the reflection point is open, L = λ/2K (K is a natural number). Apparatus according to claim 1, which satisfies the claims. 3. Let the wavelength of the output of any microwave oscillator be λ, and the distance between the corresponding branch point and the reflection point be L. If the reflection point is a shot, then L = λ/4M (M is an odd number). Apparatus according to claim 1, which satisfies the claims.