Narrow-band U-shaped amplitude equalization circuit

Abstract

The invention discloses a narrowband U-shaped amplitude equalization circuit, which has the characteristics of simple structure and small insertion loss. An input port and an output port of the equalization circuit are reciprocal, and a circuit formed by connecting a first resonator, a second resonator and a resistor in series is connected to a signal transmission main line in parallel. The first resonator and the second resonator are similar in structure, each resonator is composed of a capacitor and an inductor which are connected in parallel to form a resonant unit, an open circuit function is achieved at the resonant frequency, a signal transmission main line is isolated from a resistor, and lossless transmission of signals is achieved. The resistor is used for absorbing energy at a non-resonant frequency to realize an amplitude equalization function, and different equalization quantities can be realized by changing a resistance value. The equalization circuit forms a curve with a U-shaped amplitude-frequency characteristic between the resonant frequency of the first resonator and the resonant frequency of the second resonator. According to the circuit, a relatively large balance amount can be realized in a relatively narrow bandwidth. The circuit is simple, reliable and practical, and is suitable for improving the flatness of the microwave circuit.

Description

Technical Field

[0001] The invention belongs to the technical field of amplitude equalization. Background Art

[0002] Affected by the actual characteristics of various components, the RF signal will be distorted during the circuit transmission process. The decline in signal quality will cause inter-code interference and increase the bit error rate. Therefore, it is necessary to compensate for the signal distortion appropriately. In actual circuits, the most common distortion is amplitude distortion, especially the introduction of high suppression filters in the circuit, which makes the signal sideband amplitude much smaller than the center frequency, increasing the difficulty of back-end signal processing and consuming more computing resources. An amplitude equalization circuit with an amplitude-frequency characteristic opposite to that of the filter is required to compensate for the distorted signal.

[0003] The amplitude-frequency curve of the commonly used equalization circuit is a single oblique line within a large bandwidth, which is not suitable for equalizing the amplitude distortion caused by the filter. In addition, most equalizers use lumped components and are implemented with PCB boards, which have problems such as low consistency in mass production and large size, and do not meet the demand for miniaturization of microwave circuits. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a narrowband U-shaped amplitude equalization circuit, which has the characteristics of simple circuit structure and small size.

[0005] The invention proposes a narrowband U-shaped amplitude equalization circuit, and the technical solution includes:

[0006] The input port and output port of the circuit are reciprocal, and the structure is bilaterally symmetrical. The signal transmission main line is connected in parallel with a circuit consisting of a first resonator S1, a second resonator S2, and a resistor R in series. One end of the first resonator S1 is connected to the signal transmission main line, and the other end is connected to the second resonator S2. The other end of the second resonator S2 is connected to the resistor R. One end of the resistor R is connected to the second resonator S2, and the other end is grounded.

[0007] Furthermore, the first resonator S1 is composed of an inductor L1 and a capacitor C1 connected in parallel;

[0008] Furthermore, the first resonator S2 is composed of an inductor L2 and a capacitor C2 connected in parallel;

[0009] Furthermore, the amplitude equalization circuit forms an amplitude-frequency characteristic curve of U shape between the resonant frequency of the first resonator and the resonant frequency of the second resonator;

[0010] Preferably, the amplitude equalization circuit is implemented using a semiconductor process based on a GaAs substrate;

[0011] Furthermore, the inductor L1 and the inductor L2 are implemented by using a square structure in GaAs semiconductor technology;

[0012] Furthermore, the capacitors C1 and C2 are implemented by MIM capacitors in GaAs semiconductor technology;

[0013] Furthermore, the resistor R is implemented by a thin film resistor in a GaAs semiconductor process.

[0014] The advantages of the present invention compared with the prior art are:

[0015] The present invention adopts a small amount of resistors, capacitors and inductors to design a narrowband U-shaped amplitude equalization circuit with simple structure, excellent performance and high reliability. Its amplitude-frequency characteristic is U-shaped, which can compensate for the signal amplitude distortion caused by the filter. It adopts GaAs semiconductor technology and has the characteristics of high integration, small size, light weight and good batch production consistency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a principle block diagram of the narrowband U-shaped amplitude equalization circuit of the present invention;

[0017] Figure 2 It is a simulated amplitude-frequency curve of the narrow-band U-shaped amplitude equalization circuit of the present invention;

[0018] Figure 3 The schematic diagram of the amplitude equalization chip based on GaAs process is preferably implemented in the present invention.

[0019] Figure 1 In the figure, L1~L2 represent inductors, C1~C2 represent capacitors, R represents a resistor, S1 represents a first resonator, and S2 represents a second resonator. DETAILED DESCRIPTION

[0020] The present invention is further explained below in conjunction with the accompanying drawings and preferred embodiments.

[0021] like Figure 1 and Figure 3 As shown, the narrowband U-shaped amplitude equalization circuit provided by the embodiment of the present invention includes: a dielectric substrate and an amplitude equalization circuit arranged on the substrate;

[0022] The narrowband U-shaped amplitude equalization circuit includes a signal input port, an amplitude equalization circuit composed of lumped elements (capacitors, inductors, resistors), and a signal output port;

[0023] The amplitude balancing circuit is a bilaterally symmetrical structure, and a circuit consisting of a first resonator S1, a second resonator S2 and a resistor R in series is connected in parallel on the signal transmission main line. One end of the first resonator S1 is connected to the signal transmission main line, and the other end is connected to the second resonator S2. The other end of the second resonator S2 is connected to the resistor R, one end of the resistor R is connected to the second resonator S2, and the other end is grounded. When the first resonator S1 or the second resonator S2 resonates, the resistor R is isolated from the transmission main line, there are no lossy components in the transmission path, and the signal is not attenuated. When the operating frequency deviates from the resonant frequency of the resonator, the resistor R is connected to the transmission main line, absorbs energy, and attenuates the signal to achieve the function of amplitude balancing.

[0024] In an optional embodiment of the present invention, the dielectric substrate is made of GaAs material with a thickness of 100 um and a dielectric constant of 12.9.

[0025] In an optional embodiment of the present invention, the first resonator S1 is composed of an inductor L1 and a capacitor C1 connected in parallel, and the resonant frequency of the first resonator S1 can be changed by changing the value of the inductor L1 or the capacitor C1.

[0026] In an optional embodiment of the present invention, the second resonator S2 is composed of an inductor L2 and a capacitor C2 connected in parallel, and the resonant frequency of the second resonator S2 can be changed by changing the value of the inductor L2 or the capacitor C2.

[0027] In an optional embodiment of the present invention, the inductor L1 and the inductor L2 are implemented using a square structure in a GaAs semiconductor process.

[0028] In an optional embodiment of the present invention, the capacitors C1 and C2 are implemented using MIM capacitors in a GaAs semiconductor process.

[0029] In an optional embodiment of the present invention, the resistor R is implemented by a thin film resistor in a GaAs semiconductor process, and different balancing amounts can be achieved by adjusting the value of the resistor R.

[0030] In an optional embodiment of the present invention, the input port Port1 and the output port Port2 are led out through a pad, and the size of the pad is 100 um×100 um.

[0031] In an optional embodiment of the present invention, there is a pad on each side of the input port Port1 and the output port Port2, and they are grounded through ground vias to form a ground-signal-ground (GSG) structure, which is convenient for testing with a probe.

[0032] The above description is only a preferred example of the present invention and is not intended to limit the present invention. Any size modification, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A narrowband U-shaped amplitude equalization circuit, characterized in that: The circuit input port and output port are reciprocal and have a bilaterally symmetrical structure. A circuit consisting of a first resonator (S1), a second resonator (S2) and a resistor (R) connected in series is connected in parallel on a signal transmission main line; one end of the first resonator (S1) is connected to the signal transmission main line, and the other end is connected to the second resonator (S2); the other end of the second resonator (S2) is connected to the resistor (R); one end of the resistor (R) is connected to the second resonator (S2), and the other end is grounded.

2. A narrowband U-shaped amplitude equalization circuit according to claim 1, characterized in that: The first resonator (S1) is composed of an inductor (L1) and a capacitor (C1) connected in parallel.

3. The narrowband U-shaped amplitude equalization circuit according to claim 1, characterized in that: The first resonator (S2) is composed of an inductor (L2) and a capacitor (C2) connected in parallel.

4. A narrowband U-shaped amplitude equalization circuit according to claim 2 or claim 3, characterized in that: The inductor (L1) and the inductor (L2) are realized by using a square structure in GaAs semiconductor technology.

5. A narrowband U-shaped amplitude equalization circuit according to claim 2 or claim 3, characterized in that: The capacitor (C1) and the capacitor (C2) are realized by using MIM capacitors in GaAs semiconductor technology.

6. A narrowband U-shaped amplitude equalization circuit according to claim 2 or claim 3, characterized in that: The resistor (R) is implemented by a thin film resistor in a GaAs semiconductor process.

7. The narrowband U-shaped amplitude equalization circuit according to claim 1, characterized in that: The circuit forms a U-shaped amplitude-frequency characteristic curve between the resonant frequency of the first resonator and the resonant frequency of the second resonator.

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