JPH0831748B2 - Non-linear signal generator - Google Patents

Description

The present invention relates to a non-linear signal generating circuit used in a non-linear compensating circuit for compensating the non-linearity of an amplifier using a predistortion method, and in particular, a diode is used as a non-linear element. The present invention relates to a non-linear compensation circuit.

[Conventional technology]

Conventionally, this type of non-linear signal generating circuit has been configured to use a circulator.

FIG. 2 shows an example of a circuit using a conventional circulator. In this configuration, an RF signal input to the input port 22 of the circulator 21 is connected to the reflection port 23 in reverse polarity as a non-linear element. One diode 24,25
And two diodes 24,2
Only the non-linear component generated by 5 appears at the output port 27.

[Problems to be solved by the invention]

In the above-described conventional non-linear signal generation circuit, since the circulator is used, the band to be used is determined by the band of the circulator, and it is difficult to widen the band. Further, since a magnet is required for the circulator, it is difficult to form a circuit with a planar circuit and it is difficult to form a microwave integrated circuit. Furthermore, it is difficult to make a circulator with the same impedance without adjustment, which also makes it difficult to form a microwave integrated circuit.

It is an object of the present invention to provide a non-linear signal generating circuit which is excellent in wide band characteristics and which can be configured by a planar circuit to easily realize a microwave integrated circuit and also to make adjustment free.

[Means for solving problems]

The non-linear signal generating circuit of the present invention is composed of a 90-degree hybrid using a distributed constant line, and two terminals connected in parallel in reverse polarity and a terminating resistor are connected between each terminal of the coupling port and the passing port and the ground. It is configured.

〔Example〕

 Next, the present invention will be described with reference to the drawings.

 FIG. 1 is a circuit diagram of an embodiment of the present invention.

As shown in the figure, in the present invention, a 90-degree hybrid is mainly constituted, an input port 2 of this 90-degree hybrid 1 is an output port 3 as an isolation port, and a coupling port 4 is connected in reverse polarity in parallel. Two diodes 5,
6 and the terminating resistor 7 are connected, and the passing port 8 is also connected with two diodes 9 and 10 and a terminating resistor 11 which are similarly connected in parallel with opposite polarities. The diodes 5 and 9 and the termination resistors 7 and 11 are grounded at high frequencies by bypass capacitors 12, 13, 14 and 15, while the diodes 6 and 10 are directly grounded.
A bias terminal 16 is provided at the connection between the diodes 5 and 9 and the bypass capacitors 13 and 14 so that a bias current can flow from there to the four diodes 5, 6, 9 and 10.

Therefore, in this configuration, the high frequency signal input to the input port 2 is divided into the coupling port 4 and the passage port 8, and each high frequency signal is divided into two diodes 5, 6 or 9, which are connected in reverse polarity in parallel. Only the non-linear signals generated by the diodes 5, 6 or 9, 10 are terminated by the 10 and the terminating resistor 7 or 11, and are combined by the 90-degree hybrid 1 to appear at the output port 3.

According to this configuration, the 90-degree hybrid is mainly configured, so that it is excellent in wide band performance. Furthermore, the 90-degree hybrid is easy to configure with a planar circuit, and it is possible to realize a microwave integrated circuit, and it is also possible to eliminate adjustment.

〔The invention's effect〕

As described above, since the present invention uses the 90-degree hybrid utilizing the distributed constant line, it has excellent broadband characteristics compared to the case of using a conventional circulator,
Furthermore, the configuration using a planar circuit is easy, and a microwave integrated circuit can be easily formed, and adjustment can be eliminated.

[Brief description of drawings]

FIG. 1 is a circuit diagram of an embodiment of the present invention, and FIG. 2 is a conventional circuit diagram. 1 ... 90 degree hybrid, 2 ... input port, 3 ... output port, 4 ... coupling port, 5,6 ... diode, 7
...... Termination resistance, 8 ...... Pass port, 9,10 ...... Diode, 11 ...... Termination resistance, 12,13,14,15 …… Bypass capacitor, 16 …… Bias terminal, 21 …… Circulator, 22
...... Input port, 23 …… Reflection port, 24,25 …… Diode, 26 …… Terminal resistor, 27 …… Output port.

Front page continuation (72) Inventor Nobuaki Imai 1-2356 Takeshi, Yokosuka City, Kanagawa Pref., Nippon Telegraph and Telephone Corporation, Second Communication Network Research Laboratory (72) Toshio Nojima 1-2356 Takeshi, Yokosuka City, Kanagawa Nippon Telegraph and Telephone Corporation Kazushige Ito, Examiner, Communication Network Research Laboratories, Inc. (56) Reference JP-A-63-9306 (JP, A)

Claims (1)

[Claims] 1. A non-linear signal generating circuit used in a non-linear compensating circuit for compensating for non-linearity of an amplifier using a predistortion method, which is mainly composed of a 90-degree hybrid using a distributed constant line and whose input port is an input. , A non-linear signal generating circuit characterized in that an isolation port is used as an output, and two diodes, which are non-linear elements and are connected in parallel in opposite polarities, and a terminating resistor are connected between each terminal of the coupling port and the passing port and the ground. .