Single-stage amplification circuit and gain high and low temperature compensation method thereof

Abstract

The invention discloses a single-stage amplification circuit and a gain high and low temperature compensation method thereof. The single-stage amplification circuit comprises an input matching network and a grid electrode feed temperature compensation network which are connected with a grid electrode of a pHEMT tube; the drain electrode of the pHEMT tube and the drain electrode feed network are respectively connected with the output matching network; the input end of the input matching network is used for inputting a radio frequency signal and converting input impedance into grid input impedance of the pHEMT tube to play a role in impedance matching; the pHEMT tube is used for amplifying a signal input into the pHEMT tube and then outputting the amplified signal to the output matching network; the output matching network is used for converting the drain impedance of the pHEMT tube into output impedance so as to realize matching of the single-stage amplification circuit and an external system, and the output impedance is equal to the input impedance; the grid feed temperature compensation network is used for providing grid voltage for the pHEMT tube; the drain electrode feed network is used for providing drain electrode voltage for the pHEMT tube. According to the invention, the consistency of high and low temperature gain of the single-stage amplification circuit is realized.

Description

Technical Field

[0001] The present application relates to the field of microwave radio frequency technology, and in particular to a single-stage amplifier circuit and a gain high and low temperature compensation method thereof. Background Art

[0002] For compound microwave monolithic amplifiers, the transconductance of the pHEMT decreases with increasing temperature, leading to a decrease in amplifier gain. The gain variation at high and low temperatures can be calculated as 0.006dB / stage / degree Celsius. For example, for a single-stage amplifier, the gain variation within the temperature range of -55°C to 85°C is approximately 0.006*140*1=0.84dB. For multi-stage amplifiers, the gain fluctuations at high and low temperatures are even greater, seriously affecting the system's dynamic performance.

[0003] Currently, a widely used measure is to cascade temperature compensation chips in the link to reduce the link's high and low temperature fluctuations. However, this method has two drawbacks. First, the temperature compensation circuit is particularly sensitive to the supply voltage, and the compensation effect is generally poor. Second, the compensation at the high and low ends of the frequency is inconsistent, making it difficult to compensate for the high and low temperature characteristics of the amplifier across the entire frequency band, resulting in unsatisfactory temperature characteristics after compensation. Summary of the Invention

[0004] In view of this, the present application provides a single-stage amplifier circuit and a gain high and low temperature compensation method thereof, which achieves gain high and low temperature consistency by adjusting the gate voltage.

[0005] The present application discloses a single-stage amplifier circuit, which includes an input matching network, a gate feed temperature compensation network, a pHEMT tube, a drain feed network, and an output matching network; the input matching network and the gate feed temperature compensation network are respectively connected to the gate of the pHEMT tube; the drain of the pHEMT tube and the drain feed network are respectively connected to the output matching network;

[0006] The input end of the input matching network is used to input the RF signal and convert the input impedance into the gate input impedance of the pHEMT tube, thus playing the role of impedance matching.

[0007] The pHEMT tube is used to amplify the input signal and output it to the output matching network;

[0008] The output matching network is used to convert the drain impedance of the pHEMT tube into output impedance, achieving matching between the single-stage amplifier circuit and the external system, and the output impedance is equal to the input impedance;

[0009] The gate feed temperature compensation network is used to provide gate voltage for the pHEMT tube;

[0010] The drain feeding network is used to provide drain voltage for the pHEMT tube.

[0011] Further, the gate feed temperature compensation network comprises a first resistor, a second resistor, a third resistor, and a plurality of Schottky barrier diodes.

[0012] One end of the second resistor is connected to a power supply, and the other end is connected to one end of the third resistor through a plurality of Schottky barrier diodes connected in series; one end of the first resistor is grounded, and the other end is connected to one end of the third resistor; the other end of the third resistor is connected to the gate of the pHEMT tube.

[0013] Further, the first resistor, the second resistor, and the plurality of Schottky barrier diodes divide the voltage of the power supply to provide a gate voltage for the pHEMT tube.

[0014] Further, the number of Schottky barrier diodes in the gate feed temperature compensation network is determined according to the requirement of temperature compensation.

[0015] Further, the gate voltage applied to the pHEMT tube at different temperatures is adjusted by the Schottky barrier diode;

[0016] When in a low-temperature environment, the voltage difference of the Schottky barrier diode increases, the voltage division of the first resistor decreases, the gate voltage applied to the gate of the pHEMT tube decreases, and the gain of the pHEMT tube is inversely pulled down, offsetting the effect of the increased transconductance of the pHEMT tube at low temperature; when in a high-temperature environment, the voltage difference of the Schottky barrier diode decreases, the voltage division of the first resistor increases, the gate voltage applied to the gate of the pHEMT tube increases, and the gain of the pHEMT tube is pulled up, offsetting the effect of the decreased transconductance of the pHEMT tube at high temperature, thereby realizing the consistency of the gain of the single-stage amplification circuit in high-temperature and low-temperature environments.

[0017] Further, the drain feed network comprises a power supply, an inductor, a first branch, and a second branch; the negative electrode of the power supply is grounded, and the positive electrode is connected to the drain of the pHEMT tube through the inductor; the first branch and the second branch are connected in parallel; the first branch comprises a first capacitor; one end of the first capacitor is connected to the positive electrode of the power supply and the common terminal of the inductor, and the other end is grounded; the second branch comprises a second capacitor; one end of the second capacitor is connected to the positive electrode of the power supply and the common terminal of the inductor, and the other end is grounded; the first branch and the second branch are used for radio frequency grounding and simultaneously enhance the stability of the single-stage amplification circuit.

[0018] Further, the pHEMT tube adopts a 0.25um gate length process, the tube selection gate width is 50um, the gate index is 4, and the temperature setting is 25℃ during normal temperature simulation.

[0019] Further, the input matching network is composed of inductors, capacitors, resistors, and transmission lines; and the output matching network is composed of inductors, capacitors, resistors, and transmission lines.

[0020] The present application also discloses a high and low temperature gain compensation method for a single-stage amplifier, which is applicable to the single-stage amplifier circuit described above and includes:

[0021] When the single-stage amplifier circuit is in a low-temperature environment, the voltage difference of the Schottky barrier diode in the gate feed temperature compensation network increases, so that the gate voltage on the pHEMT tube gate decreases, and the gain of the pHEMT tube is reversely pulled down, offsetting the effect of the increase in low-temperature transconductance;

[0022] When the single-stage amplifier circuit is in a high-temperature environment, the voltage difference of the Schottky barrier diode in the gate feed temperature compensation network decreases, so that the gate voltage on the gate of the pHEMT tube increases, and the gain of the pHEMT tube is reversely pulled up, offsetting the effect of the reduction of high-temperature transconductance, thereby achieving consistency in the gain of the single-stage amplifier circuit in high and low-temperature environments.

[0023] Due to the adoption of the above-mentioned technical solution, the present application has the following advantages: by connecting multiple Schottky barrier diodes in series, the high and low temperature variation of the gain is narrowed, and further increasing the number of Schottky barrier diodes can further improve the high and low temperature fluctuations, and even achieve low-temperature gain lower than high-temperature gain, thereby compensating for the high and low temperature fluctuations of the entire RF link. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments recorded in the embodiments of the present application. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0025] Figure 1 This is a schematic diagram of a single-stage amplifier circuit in an embodiment of the present application;

[0026] Figure 2 is the drain feed circuit used in the embodiments of the present application;

[0027] Figure 3 This is a gate feeding circuit diagram in an embodiment of the present application in which temperature compensation is not used;

[0028] Figure 4 This is the high and low temperature gain curve in the embodiment of the present application where temperature compensation is not used;

[0029] Figure 5 This is a gate feed circuit diagram using temperature compensation in an embodiment of the present application;

[0030] Figure 6 This is the high and low temperature gain curve using temperature compensation in the embodiment of the present application. DETAILED DESCRIPTION

[0031] The present application is further described with reference to the accompanying drawings and embodiments. The embodiments described are only a part of the embodiments of the present application, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field should fall within the scope of protection of the embodiments of the present application.

[0032] See also Figure 1 The present application provides an embodiment of a single-stage amplifier circuit, which includes an input matching network, a gate feed temperature compensation network, a pHEMT tube, a drain feed network, and an output matching network; the input matching network and the gate feed temperature compensation network are respectively connected to the gate of the pHEMT tube; the drain of the pHEMT tube and the drain feed network are respectively connected to the output matching network;

[0033] The input end of the input matching network is used to input the RF signal and convert the input impedance into the gate input impedance of the pHEMT tube, thus playing the role of impedance matching.

[0034] The pHEMT tube is used to amplify the input signal and output it to the output matching network;

[0035] The output matching network is used to convert the drain impedance of the pHEMT tube into output impedance, achieving matching between the single-stage amplifier circuit and the external system, and the output impedance is equal to the input impedance;

[0036] The gate feed temperature compensation network is used to provide gate voltage for the pHEMT tube;

[0037] The drain feeding network is used to provide drain voltage for the pHEMT tube.

[0038] Optionally, the gate feed temperature compensation network includes a first resistor, a second resistor, a third resistor, and a plurality of Schottky barrier diodes;

[0039] One end of the second resistor is connected to the power supply, and the other end is connected to one end of the third resistor through multiple Schottky barrier diodes connected in series; one end of the first resistor is grounded, and the other end is connected to one end of the third resistor; the other end of the third resistor is connected to the gate of the pHEMT tube.

[0040] Optionally, the first resistor, the second resistor, and the plurality of Schottky barrier diodes divide the power supply voltage to provide a gate voltage to the pHEMT tube.

[0041] Optionally, the number of Schottky barrier diodes in the gate feed temperature compensation network is determined according to temperature compensation requirements.

[0042] Optionally, the gate voltage applied to the pHEMT tube at different temperatures is adjusted by a Schottky barrier diode;

[0043] When in a low-temperature environment, the voltage difference of the Schottky barrier diode increases, the voltage divided by the first resistor decreases, the gate voltage connected to the gate of the pHEMT tube decreases, and the gain of the pHEMT tube is reversely pulled down, offsetting the increase in transconductance of the low-temperature pHEMT tube; when in a high-temperature environment, the voltage difference of the Schottky barrier diode decreases, the voltage divided by the first resistor increases, the gate voltage connected to the gate of the pHEMT tube increases, and the gain of the pHEMT tube is pulled up, offsetting the decrease in transconductance of the high-temperature pHEMT tube, thereby achieving consistency in gain of the single-stage amplifier circuit in high and low-temperature environments.

[0044] Optionally, the drain feeding network includes a power supply, an inductor, a first branch, and a second branch; the negative pole of the power supply is grounded, and the positive pole is connected to the drain of the pHEMT tube through the inductor; the first branch and the second branch are connected in parallel; the first branch includes a first capacitor; one end of the first capacitor is connected to the positive pole of the power supply and the common end of the inductor, and the other end is grounded; the second branch includes a second capacitor; one end of the second capacitor is connected to the positive pole of the power supply and the common end of the inductor, and the other end is grounded; the first branch and the second branch are used for RF grounding, while enhancing the stability of the single-stage amplifier circuit.

[0045] Optionally, the input matching network consists of an inductor, a capacitor, a resistor and a transmission line; and the output matching network consists of an inductor, a capacitor, a resistor and a transmission line.

[0046] The present application also provides an embodiment of a high-low temperature compensation method for a single-stage amplifier gain, which is applicable to the single-stage amplifier circuit described in the above embodiment, and includes:

[0047] When the single-stage amplifier circuit is in a low-temperature environment, the voltage difference of the Schottky barrier diode in the gate feed temperature compensation network increases, so that the gate voltage on the pHEMT tube gate decreases, and the gain of the pHEMT tube is reversely pulled down, offsetting the effect of the increase in low-temperature transconductance;

[0048] When the single-stage amplifier circuit is in a high-temperature environment, the voltage difference of the Schottky barrier diode in the gate feed temperature compensation network decreases, so that the gate voltage on the gate of the pHEMT tube increases, and the gain of the pHEMT tube is reversely pulled up, offsetting the effect of the reduction of high-temperature transconductance, thereby achieving consistency in the gain of the single-stage amplifier circuit in high and low-temperature environments.

[0049] The source of the pHEMT tube in the embodiment of the present application is grounded, and its corresponding parameters are: gate length Ig=0.25um, gate width wg=50um, gate index nf=4, and temperature ta=25°C during normal temperature simulation.

[0050] Figure 1This is a block diagram of the principle of a single-stage amplifier circuit, including a gate feed network, a drain feed network, a pHEMT tube, an input matching network, and an output matching network. After the RF signal is input, the input matching network converts the 50 ohm impedance into the gate input impedance of the pHEMT, performing impedance matching. The signal is amplified by the pHEMT and output. The output matching network converts the pHEMT's drain impedance to 50 ohms, achieving matching between the single-stage amplifier circuit and the external system. The input and output matching networks are generally composed of inductors, capacitors, resistors, and transmission lines. The gate feed network and drain feed network provide the gate voltage and drain voltage for the pHEMT, respectively.

[0051] Figure 2 For the drain feeding network, the +5V power supply voltage is connected to the drain of the pHEMT tube through the inductor L. At the same time, two bypass capacitors C1 and C2 are added for RF grounding and to enhance the stability of the amplifier;

[0052] Figure 3 This is the gate feed network. The circuit does not add a temperature compensation structure. Resistor R1 = 5050Ω, resistor R2 = 11000Ω, resistor R3 = 1000Ω, and resistor R4 = 20000Ω. +5V extracts 700mV of voltage through the voltage divider resistor to provide gate voltage for the pHEMT amplifier tube.

[0053] Figure 4 Figure 3 shows the gain curves of the amplifier at -55°C (low temperature), 25°C (normal temperature), and 85°C (high temperature) without adding temperature compensation. The curve with squares represents the gain at 25°C, the curve with diamonds represents the gain at 85°C, and the curve with dots represents the gain curve at -55°C. It can be seen from the three gain curves that the gain curve fluctuates by 0.7dB at high and low temperatures. Figure 4 The horizontal axis is the frequency freq, the unit is frequency MHZ, and the vertical axis is the gain S(2,1), the unit is dB.

[0054] Figure 5 A temperature compensation structure is added to the gate feed network, where resistor R1 = 5050Ω, resistor R2 = 7000Ω, and resistor R3 = 1000Ω. Figure 5 It can be seen that Figure 3The resistor R4 is replaced by four Schottky barrier diodes (Diode1, Diode2, Diode3, Diode4) connected in series (different numbers of Schottky barrier diodes are selected according to the temperature compensation requirements). The gate voltage applied to the pHEMT amplifier tube at different temperatures can be adjusted through the diode. At low temperatures, the voltage difference between the diodes increases, and the voltage divided by the ground resistor (gate voltage) decreases, thereby reducing the increase in gain of the pHEMT amplifier tube due to the increase in transconductance at low temperatures. At high temperatures, the voltage difference between the diodes decreases, and the voltage divided by the ground resistor (gate voltage) increases, thereby increasing the gain decrease caused by the decrease in transconductance of the pHEMT amplifier tube at high temperatures, thereby ultimately reducing the fluctuation of high and low temperature gains.

[0055] Figure 6 To add the gain curves of the compensation structure amplifier at -55℃, 25℃ and 85℃, the curve with squares represents the gain at 25℃, the curve with diamonds represents the gain at 85℃, and the curve with circles represents the gain curve at -55℃. It can be seen from the three gain curves that the gain curve fluctuates by 0.2dB at high and low temperatures, which is optimized by 0.5dB, greatly improving the consistency of the amplifier's high and low temperature gain. Figure 6 The horizontal axis is the frequency freq, the unit is frequency MHZ, and the vertical axis is the gain S(2,1), the unit is dB.

[0056] Amplifiers designed with feed compensation networks can achieve good high and low temperature gain consistency and have been used on a large scale in multiple projects, producing good economic benefits.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and not to limit them. Although the present application has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present application can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present application should be included in the scope of protection of the claims of the present application.

Claims

1. A single-stage amplifier circuit, characterized in that: It includes an input matching network, a gate feed temperature compensation network, a pHEMT tube, a drain feed network and an output matching network; the input matching network and the gate feed temperature compensation network are respectively connected to the gate of the pHEMT tube; the drain of the pHEMT tube and the drain feed network are respectively connected to the output matching network; The input end of the input matching network is used to input the RF signal and convert the input impedance into the gate input impedance of the pHEMT tube, thus playing the role of impedance matching. The pHEMT tube is used to amplify the input signal and output it to the output matching network; The output matching network is used to convert the drain impedance of the pHEMT tube into output impedance, achieving matching between the single-stage amplifier circuit and the external system, and the output impedance is equal to the input impedance; The gate feed temperature compensation network is used to provide gate voltage for the pHEMT tube; The drain feeding network is used to provide drain voltage for the pHEMT tube.

2. The single-stage amplifier circuit according to claim 1, characterized in that: The gate feed temperature compensation network includes a first resistor, a second resistor, a third resistor, and a plurality of Schottky barrier diodes; One end of the second resistor is connected to the power supply, and the other end is connected to one end of the third resistor through multiple Schottky barrier diodes connected in series; one end of the first resistor is grounded, and the other end is connected to one end of the third resistor; the other end of the third resistor is connected to the gate of the pHEMT tube.

3. The single-stage amplifier circuit according to claim 2, characterized in that: The first resistor, the second resistor and the plurality of Schottky barrier diodes divide the power supply voltage to provide a gate voltage for the pHEMT tube.

4. The single-stage amplifier circuit according to claim 2, characterized in that: The number of Schottky barrier diodes in the gate feed temperature compensation network is determined according to the temperature compensation requirements.

5. The single-stage amplifier circuit according to claim 3, characterized in that: The gate voltage applied to the pHEMT tube at different temperatures is adjusted by the Schottky barrier diode; When in a low-temperature environment, the voltage difference of the Schottky barrier diode increases, the voltage divided by the first resistor decreases, the gate voltage connected to the gate of the pHEMT tube decreases, and the gain of the pHEMT tube is reversely pulled down, offsetting the increase in transconductance of the low-temperature pHEMT tube; when in a high-temperature environment, the voltage difference of the Schottky barrier diode decreases, the voltage divided by the first resistor increases, the gate voltage connected to the gate of the pHEMT tube increases, and the gain of the pHEMT tube is pulled up, offsetting the decrease in transconductance of the high-temperature pHEMT tube, thereby achieving consistency in gain of the single-stage amplifier circuit in high and low-temperature environments.

6. The single-stage amplifier circuit according to claim 1, characterized in that: The drain feeding network includes a power supply, an inductor, a first branch, and a second branch; the negative electrode of the power supply is grounded, and the positive electrode is connected to the drain of the pHEMT tube through the inductor; the first branch and the second branch are connected in parallel; the first branch includes a first capacitor; one end of the first capacitor is connected to the positive electrode of the power supply and the common end of the inductor, and the other end is grounded; the second branch includes a second capacitor; one end of the second capacitor is connected to the positive electrode of the power supply and the common end of the inductor, and the other end is grounded; the first branch and the second branch are used for radio frequency grounding, while enhancing the stability of the single-stage amplifier circuit.

7. The single-stage amplifier circuit according to claim 1, characterized in that: The pHEMT tube adopts a 0.25um gate length process, a gate width of 50um, a gate index of 4, and a temperature of 25°C during normal temperature simulation.

8. The single-stage amplifier circuit according to claim 1, wherein: The input matching network is composed of an inductor, a capacitor, a resistor and a transmission line; the output matching network is composed of an inductor, a capacitor, a resistor and a transmission line.

9. A method for compensating the gain of a single-stage amplifier at high and low temperatures, applicable to the single-stage amplifier circuit according to any one of claims 1 to 8, characterized in that: include: When the single-stage amplifier circuit is in a low-temperature environment, the voltage difference of the Schottky barrier diode in the gate feed temperature compensation network increases, so that the gate voltage on the pHEMT tube gate decreases, and the gain of the pHEMT tube is reversely pulled down, offsetting the effect of the increase in low-temperature transconductance; When the single-stage amplifier circuit is in a high-temperature environment, the voltage difference of the Schottky barrier diode in the gate feed temperature compensation network decreases, so that the gate voltage on the gate of the pHEMT tube increases, and the gain of the pHEMT tube is reversely pulled up, offsetting the effect of the reduction of high-temperature transconductance, thereby achieving consistency in the gain of the single-stage amplifier circuit in high and low-temperature environments.

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