Broadband high-dynamic detection circuit

Abstract

The utility model relates to the field of microwave communication, in particular to a broadband high-dynamic detection circuit. Comprising a first voltage-controlled attenuator, a first amplifier, a second voltage-controlled attenuator, a temperature compensation attenuator, a second amplifier, a third voltage-controlled attenuator, a third amplifier, a detector and an operational amplifier which are connected in sequence, the input end of the first voltage-controlled attenuator is used for receiving a radio frequency signal; the input end of the operational amplifier is connected with the output end of the detector, the first output end of the operational amplifier is respectively connected with the control ends of the first voltage-controlled attenuator, the second voltage-controlled attenuator and the third voltage-controlled attenuator and is used for dynamically adjusting signal gain, and the second output end of the operational amplifier is used for outputting detection voltage; the temperature compensation attenuator is used for correcting gain difference caused by temperature change in real time. According to the utility model, the voltage-controlled attenuator is controlled in an AGC mode, so that broadband high-dynamic signal detection is realized, and the problems of insufficient dynamic range, bandwidth, linearity and temperature stability in the prior art are effectively solved.

Description

Technical Field

[0001] This utility model relates to the field of microwave communication, specifically to a broadband high dynamic detection circuit. Background Technology

[0002] With the rapid development of microwave electronics technology, the technical requirements for communication systems, radar signal processing, and electronic measuring instruments are becoming increasingly stringent, especially regarding the dynamic range, bandwidth, linearity, and temperature stability of signal detection. Traditional detection techniques have limitations in terms of dynamic range and bandwidth, making it difficult to meet the demands of modern communication and radar systems for high-sensitivity receivers. For example, while existing high-dynamic automatic gain control circuits can achieve a certain dynamic range, their bandwidth and temperature stability still need improvement.

[0003] Prior art document CN218998025U discloses a broadband high-dynamic automatic gain control circuit, which is implemented by cascading three high-gain signal amplifiers with three large-dynamic voltage-controlled attenuators. While it can meet the dynamic range requirements to a certain extent, it has shortcomings in temperature compensation and detection accuracy. This leads to difficulties in guaranteeing signal stability and accuracy in practical applications, especially in environments with large temperature variations, thus affecting the overall system performance. Utility Model Content

[0004] The purpose of this invention is to provide a broadband high dynamic range detector circuit to solve the problems of insufficient dynamic range, bandwidth, linearity and temperature stability in the prior art.

[0005] To achieve the above objectives, the following technical solution is adopted.

[0006] A broadband high dynamic range detector circuit includes a first voltage-controlled attenuator, a first amplifier, a second voltage-controlled attenuator, a temperature-compensated attenuator, a second amplifier, a third voltage-controlled attenuator, a third amplifier, a detector, and an operational amplifier connected in sequence.

[0007] The input terminal of the first voltage-controlled attenuator is used to receive radio frequency signals; the input terminal of the operational amplifier is connected to the output terminal of the detector, and the first output terminal of the operational amplifier is connected to the control terminals of the first voltage-controlled attenuator, the second voltage-controlled attenuator and the third voltage-controlled attenuator respectively, for dynamically adjusting the signal gain; the second output terminal of the operational amplifier is used to output the detection voltage; the temperature-compensated attenuator is used to correct the gain difference caused by temperature changes in real time.

[0008] Optionally, the first voltage-controlled attenuator, the second voltage-controlled attenuator, and the third voltage-controlled attenuator operate at frequencies from 50MHz to 18000MHz; the maximum attenuation is greater than 30dB; and the control voltage is a +5V operating voltage.

[0009] Optionally, the first amplifier has a gain of 30dB and a noise figure of ≤2.4dB.

[0010] Optionally, the attenuation of the temperature-compensated attenuator varies with temperature as follows: 5 dB at room temperature, 8.75 dB at low temperature, and 2.94 dB at high temperature.

[0011] Optionally, the gain of the second amplifier is 35dB, and its phase noise degradation does not exceed a preset threshold.

[0012] Optionally, the gain of the third amplifier is 25dB, and its phase noise degradation does not exceed a preset threshold.

[0013] Optionally, the detector is a broadband RMS detector with a dynamic range ≥60dB, a detection frequency covering 50MHz to 12000MHz, and a detection error ≤±0.5dB.

[0014] Optionally, the operational amplifier has an offset voltage ≤ ±5μV, a common-mode rejection ratio ≥140dB, and a noise density ≤5.5nV / √Hz at a frequency of 1kHz.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] This invention achieves broadband, high-dynamic signal detection by employing AGC (Automatic Gain Control) mode to control the voltage-controlled attenuator, effectively solving the problems of insufficient dynamic range, bandwidth, linearity, and temperature stability in existing technologies. Specifically, through a multi-stage cascaded structure and the use of a temperature-compensated attenuator, the dynamic range and temperature stability of the signal are optimized, ensuring a linear response of the overall circuit within the input signal amplitude range of -70dBm to +20dBm. This not only improves signal stability and accuracy but also simplifies the circuit structure and spatial layout, reducing costs.

[0017] Furthermore, this invention further optimizes the circuit performance. The operating frequency range and maximum attenuation capability of the voltage-controlled attenuator ensure the wide bandwidth characteristics of the circuit. The high gain and low noise figure of the amplifier improve the signal transmission quality and accuracy. The precise temperature compensation of the temperature-compensated attenuator further enhances the temperature stability of the circuit. The high dynamic range and low detection error of the detector improve detection accuracy. The low offset voltage and high common-mode rejection ratio of the operational amplifier ensure the accuracy and stability of signal processing. The combination of these technical features makes this invention superior to existing technologies in terms of dynamic range, bandwidth, linearity, and temperature stability, providing a more efficient and reliable solution for communication systems, radar signal processing, and other fields. Attached Figure Description

[0018] Figure 1This is a schematic diagram of the overall structure of an embodiment of a broadband high dynamic detection circuit according to the present invention. Detailed Implementation

[0019] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0020] The following detailed description is exemplary and intended to provide further detailed explanation of the present invention. Unless otherwise specified, all technical terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. The terminology used in this invention is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to the present invention.

[0021] like Figure 1 As shown, this utility model relates to a broadband high dynamic range detector circuit. Its core lies in achieving dynamic signal adjustment and temperature compensation through a multi-stage cascaded structure and a temperature-compensated attenuator, thereby optimizing the signal's dynamic range, bandwidth, linearity, and temperature stability. The following is a detailed description of the specific embodiments of this utility model:

[0022] This utility model's broadband high dynamic range detection circuit includes a first voltage-controlled attenuator, a first amplifier, a second voltage-controlled attenuator, a temperature-compensated attenuator, a second amplifier, a third voltage-controlled attenuator, a third amplifier, a detector, and an operational amplifier connected in sequence. The RF signal input terminal is connected to the input terminal of the first voltage-controlled attenuator. After multi-stage processing, the final output voltage is obtained through the operational amplifier. The first output terminal of the operational amplifier is connected to the control terminals of the first, second, and third voltage-controlled attenuators, respectively, for dynamically adjusting the signal gain.

[0023] The voltage-controlled attenuator (VCO) is one of the key components of this circuit. It operates within a frequency range of 50MHz to 18000MHz, has a maximum attenuation capability greater than 30dB, and a control voltage of +5V. These VCOs dynamically adjust the signal gain by receiving feedback signals from the operational amplifier to ensure signal stability under different input amplitudes. In practical applications, the VCO can automatically adjust the attenuation based on the strength of the input signal, thereby achieving automatic gain control (AGC) functionality.

[0024] The first amplifier has a gain of 30dB and a noise figure controlled below 2.4dB. The second and third amplifiers have gains of 35dB and 25dB respectively, and do not degrade the phase noise of the signal during amplification. These amplifiers function as a step-by-step amplifiers of the signal in the circuit, while maintaining high-quality signal transmission.

[0025] Temperature-compensated attenuators (TCAs) function to compensate for temperature variations in circuits. Their attenuation varies with temperature: 5 dB at room temperature, 8.75 dB at low temperatures, and 2.94 dB at high temperatures. This design effectively corrects for gain differences caused by temperature variations, ensuring the circuit's performance stability under different ambient temperatures.

[0026] The detector employs a wideband RMS detector with a dynamic range of 60dB, covering a detection frequency range of 50MHz to 12000MHz, and a detection error controlled within ±0.5dB. After converting the RF signal into a voltage signal, the detector processes it through an operational amplifier. The operational amplifier's offset voltage is controlled within ±5μV, its common-mode rejection ratio reaches 140dB, and its noise density at 1kHz does not exceed 5.5nV / √Hz. The operational amplifier feeds the processed voltage signal back to the voltage-controlled attenuator for dynamic gain adjustment; it also outputs the detected voltage as the final output of the circuit.

[0027] Through the above design, this circuit can maintain a linear response within an input signal amplitude range of -70dBm to +20dBm. This wide dynamic range design allows the circuit to adapt to various signal strength variations while maintaining high-precision detection performance.

[0028] The circuit design of this invention not only optimizes the dynamic range, bandwidth, linearity, and temperature stability of the signal, but also simplifies the circuit structure and spatial layout. In practical applications, the circuit can be expanded and optimized according to different needs. For example, the dynamic range and bandwidth of the circuit can be further improved by adding more voltage-controlled attenuators and cascading amplifiers. In addition, the performance of the circuit under extreme temperature conditions can be improved by optimizing the design of the temperature-compensated attenuator.

[0029] In summary, the broadband high dynamic range detector circuit of this invention achieves dynamic signal adjustment and temperature compensation through a multi-stage cascaded structure and a temperature-compensated attenuator, optimizing the signal's dynamic range, bandwidth, linearity, and temperature stability. This circuit is simple in design, low in cost, and has broad application prospects.

[0030] As is known from common technical knowledge, this utility model can be implemented through other embodiments that do not depart from its spirit or essential characteristics. Therefore, the disclosed embodiments described above are merely illustrative in all respects and are not the only ones. All modifications within the scope of this utility model or its equivalents are included in this utility model.

Claims

1. A broadband high dynamic range detector circuit, characterized in that, The system comprises a first voltage-controlled attenuator, a first amplifier, a second voltage-controlled attenuator, a temperature-compensated attenuator, a second amplifier, a third voltage-controlled attenuator, a third amplifier, a detector, and an operational amplifier connected in sequence. The input terminal of the first voltage-controlled attenuator is used to receive radio frequency signals; the input terminal of the operational amplifier is connected to the output terminal of the detector, and the first output terminal of the operational amplifier is connected to the control terminals of the first voltage-controlled attenuator, the second voltage-controlled attenuator and the third voltage-controlled attenuator respectively, for dynamically adjusting the signal gain; the second output terminal of the operational amplifier is used to output the detection voltage; the temperature-compensated attenuator is used to correct the gain difference caused by temperature changes in real time.

2. The broadband high dynamic range detector circuit according to claim 1, characterized in that, The first, second, and third voltage-controlled attenuators all operate at frequencies between 50MHz and 18000MHz; the maximum attenuation is greater than 30dB; and the control voltage is +5V.

3. The broadband high dynamic range detector circuit according to claim 1, characterized in that, The first amplifier has a gain of 30dB and a noise figure of ≤2.4dB.

4. The broadband high dynamic range detector circuit according to claim 1, characterized in that, The attenuation of the temperature-compensated attenuator varies with temperature as follows: 5 dB at room temperature, 8.75 dB at low temperature, and 2.94 dB at high temperature.

5. A broadband high dynamic range detector circuit according to claim 1, characterized in that, The gain of the second amplifier is 35dB, and its phase noise degradation does not exceed a preset threshold.

6. The broadband high dynamic range detector circuit according to claim 1, characterized in that, The third amplifier has a gain of 25dB and its phase noise degradation does not exceed a preset threshold.

7. The broadband high dynamic range detector circuit according to claim 1, characterized in that, The detector is a broadband RMS detector with a dynamic range ≥60dB, a detection frequency range of 50MHz to 12000MHz, and a detection error ≤±0.5dB.

8. A broadband high dynamic range detector circuit according to claim 1, characterized in that, The operational amplifier has an offset voltage ≤ ±5μV, a common-mode rejection ratio ≥140dB, and a noise density ≤5.5nV / √Hz at 1kHz.

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