Ultra-wideband low-power frequency hopping filter

Abstract

The utility model discloses an ultra-wideband low-power frequency hopping filter, comprising a high-voltage switching circuit; wherein the high-voltage switching circuit comprises a single-path 2-input AND gate chip U2, capacitors C1 and C2, a triode Q3, and resistors R2, R4, R5, R6 and R9; two ends of the resistor R9 are respectively connected with an output pin of the single-path 2 input AND gate chip U2 and a base electrode of the triode Q3; the emitter of the triode Q3 is grounded; one end of the resistor R5 and the resistor R6 after being connected in parallel is connected with the collector of the triode Q3, and the other end is connected with the resonant circuit; after the resistor R2 and the resistor R4 are connected in parallel, one end is connected with the resonant circuit, and the other end is grounded after being connected with the capacitor C1; and one end of the capacitor C2 is connected with the power supply pin of the single-path 2-input AND gate chip U2, and the other end of the capacitor C2 is grounded. The high-voltage switching circuit provided by the utility model reduces the reverse cut-off voltage when the PIN diode works, and achieves the effects of improving the reliability of the PIN diode and providing a wider selection space for reselection of the PIN diode in the frequency band.

Description

TECHNICAL FIELD

[0001] The utility model relates to filter technical field, concretely is a kind of ultra-wideband low-power frequency hopping filter. BACKGROUND

[0002] Ultra-wideband low-power frequency hopping filter covers frequency 108-1950MHz, is generally divided into four frequency bands, i.e. 108-225MHz, 225-512MHz, 512-678MHz and 1300-1950MHz;Frequency band selection is controlled by frequency band control code A8 and A9, when A8=0, A9=0, select frequency band 108-225MHz;A8=1, A9=0, select frequency band 225-512MHz;A8=0, A9=1, select frequency band 512-678MHz;A8=1, A9=1, select frequency band 1300-1950MHz. Limited by product size, four frequency bands can only share a set of drive control circuit, i.e. using unified high-voltage network. The resonant loop of 108-225MHz frequency band, 225-512MHz frequency band, 512-678MHz frequency band uses PIN tube voltage division mode as shown in Figure 1 PIN tube reverse-biased cutoff voltage is half of high-voltage network. And 1300-1950MHz frequency band, because of high frequency, is affected by PIN tube junction capacitance, cannot use two PIN tube voltage division mode, can only adopt single PIN tube mode as shown in Figure 2 Therefore, the reverse-biased cutoff voltage on PIN tube is equal to the voltage of high-voltage network, due to the multiplication of PIN tube cutoff voltage, the PIN tube of 1300-1950MHz frequency band is reduced in rating, and the reliability is reduced, which also seriously restricts the re-selection of PIN tube model in this frequency band. INVENTION CONTENTS

[0003] The technical problem to be solved by the utility model lies in: providing a simple and practical high-voltage switching circuit, which aims to not significantly increase the number of control circuit components, reduce the working voltage of high-frequency resonant loop, improve the reliability of PIN tube operation, and increase the selection of PIN tube model types.

[0004] To solve the above technical problems, the utility model provides the following technical scheme:

[0005] An ultra-wideband low-power frequency hopping filter, comprising: a high-voltage switching circuit;Wherein, the high-voltage switching circuit comprises: a single 2-input AND gate chip U2, capacitors C1 and C2, a transistor Q3, resistors R2, R4, R5, R6 and R9;

[0006] The other end of the resistance R5 and the resistance R6 in parallel is connected with the collector of the transistor Q3, and the other end is connected with the resonance circuit.

[0007] The other end of the resistance R2 and the resistance R4 in parallel is connected with the resonance circuit, and the other end is connected with the capacitor C1 and then grounded.

[0008] One end of the capacitor C2 is connected with the power supply pin of the single-channel 2 input and gate chip U2, and the other end is grounded.

[0009] In this embodiment, the resistance values of the resistances R2, R4, R5 and R6 are the same.

[0010] In this embodiment, the input pin of the single-channel 2 input and gate chip U2 is connected with the frequency band signal.

[0011] In this embodiment, the frequency hopping filter includes a single-channel driving circuit connected with a high-voltage switching circuit; wherein the single-channel driving circuit includes transistors Q1, Q2 and Q4, resistances R1, R3, R7 and R8.

[0012] The resistance R1 and the resistance R3 are connected in series, and the series connection end of the resistance R1 and the resistance R3 is connected with the other end of the resistance R5 and the resistance R6 in parallel, the resistance R1 is also connected with the collector of the transistor Q1, and the resistance R3 is also connected with the base of the transistor Q1 and the collector of the transistor Q2.

[0013] One end of the resistance R7 is connected with the base of the transistor Q2, and the other end of the resistance R8 is connected with the base of the transistor Q4.

[0014] The emitter of the transistor Q2 and the emitter of the transistor Q4 are grounded; the emitter of the transistor Q1 is connected with the collector of the transistor Q4, and is connected with the resonance circuit; the other end of the resistance R7 is connected with the input level signal.

[0015] In this embodiment, the resonance circuit includes a low-frequency resonance circuit; the low-frequency resonance circuit includes blocking capacitors C57 and C58, voltage dividing resistors R77 and R78, diodes D21 and D22, and a resonance capacitor C77.

[0016] The voltage dividing resistor R77 is connected with the diode D21 in parallel, and the voltage dividing resistor R78 is connected with the diode D22 in parallel.

[0017] The cathode of the diode D21 and the anode of the diode D22 are both connected with the resonance capacitor C77.

[0018] The anode of the diode D21 is connected with the blocking capacitor C57 and then grounded, and the cathode of the diode D22 is connected with the blocking capacitor C58 and then grounded.

[0019] The cathode of the diode D22 is connected with the emitter of the triode Q1 and the collector of the triode Q4.

[0020] In the embodiment, the resistance values of the voltage dividing resistors R77 and R78 are the same.

[0021] In the embodiment, the resonant circuit comprises a high-frequency resonant circuit comprising a diode VD1, a DC blocking capacitor C5, a resonant capacitor C15 and a high-frequency inductor L3.

[0022] One end of the high-frequency inductor L3 is connected with a power supply, and the other end is connected with the anode of the diode VD1 and the resonant capacitor C15, and the cathode of the diode VD1 is connected with the DC blocking capacitor C5 and then grounded.

[0023] The cathode of the diode VD1 is connected with the emitter of the triode Q1 and the collector of the triode Q4.

[0024] Compared with the prior art, the utility model has the beneficial effects that:

[0025] The high-voltage switching circuit reduces the reverse breakdown voltage of the PIN diode in the resonant circuit during operation, improves the reliability of the PIN tube, and provides a wider selection space for the PIN tube of the frequency band. The high-voltage switching circuit does not significantly increase the number of control circuit components, reduces the operating voltage of the high-frequency resonant circuit, improves the reliability of the PIN tube in the resonant circuit, and increases the selection of PIN tube types. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 The utility model discloses a low-frequency resonant circuit schematic diagram.

[0027] Figure 2 The utility model discloses a high-frequency resonant circuit schematic diagram.

[0028] Figure 3 The utility model discloses a high-voltage switching circuit schematic diagram.

[0029] Figure 4 The utility model discloses a single drive circuit schematic diagram. DETAILED DESCRIPTION

[0030] In order to facilitate those skilled in the art to understand the technical scheme of the utility model, the technical scheme of the utility model will be further described in conjunction with the drawings of the specification.

[0031] The terms "first", "second", "third", etc. are used only for descriptive purposes and should not be construed as implying relative importance or a meaning that the described features are limited to the number of times they are used. Thus, features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality" is two or more, unless otherwise explicitly specified.

[0032] Referring to Figure 3 As shown in the figure, the utility model provides a kind of super wideband low-power frequency hopping filter, comprising: high voltage switching circuit. Among them, high voltage switching circuit includes: single 2 input and gate chip U2, capacitor C1, C2, triode Q3, resistance R2, R4, R5, R6, R9.

[0033] In the embodiment, the two ends of resistance R9 are respectively connected with the output pin of single 2 input and gate chip U2 and the base of triode Q3;The emitter of triode Q3 is grounded. One end of the parallel connection of resistance R5 and resistance R6 is connected with the collector of triode Q3, and the other end is connected with resonance circuit. One end of the parallel connection of resistance R2 and resistance R4 is connected with resonance circuit, and the other end is connected with capacitor C1 and then grounded. One end of capacitor C2 is connected with the power supply pin of single 2 input and gate chip U2, and the other end is grounded.

[0034] In the embodiment, the model of single 2 input and gate chip U2 is SN74AHC1G08DCKR, and the model of triode Q3 is MMSTA42-7-F. The input pin of single 2 input and gate chip U2 is connected with frequency band signal, that is, connected with frequency band control code A8 and A9.

[0035] Referring to Figure 4 As shown in the figure, in the embodiment, the super wideband low-power frequency hopping filter further comprises a single drive circuit connected with the high voltage switching circuit. Among them, the single drive circuit includes triodes Q1, Q2, Q4, resistances R1, R3, R7, R8.

[0036] Resistance R1 and R3 are connected in series, and the series connection end of resistance R1 and R3 is connected with the other end of the parallel connection of resistance R5 and resistance R6. Resistance R1 is also connected with the collector of triode Q1, and resistance R3 is also connected with the base of triode Q1 and the collector of triode Q2. One end of resistance R7 is connected with the base of triode Q2, and the two ends of resistance R8 are respectively connected with the other end of resistance R7 and the base of triode Q4. The emitter of triode Q2 and the emitter of triode Q4 are grounded;The emitter of triode Q1 is connected with the collector of triode Q4, and is connected with resonance circuit, and the other end of resistance R7 is connected with input level signal.

[0037] In the embodiment, the signal of triode Q1, Q2 and Q4 is also, for example, MMSTA42-7-F.

[0038] In the embodiment, the single-channel drive circuit is connected to the high-voltage network VHB, the circuit input end DI is connected to the circuit control signal, and the circuit output end DO is connected to the PIN diode cathode of the resonance circuit. When the input level signal is high, the circuit output end voltage DO is 0V; when the input level signal is low, the circuit output end voltage DO is high voltage VHB.

[0039] Please refer to Figure 1 and Figure 2 In the embodiment, the resonance circuit includes a low-frequency resonance circuit and a high-frequency resonance circuit. The low-frequency band of the low-frequency resonance circuit includes 108-225MHz, 225-512MHz and 512-678MHz bands, and each low-frequency resonance circuit includes two PIN diodes, two voltage dividing resistors, two DC blocking capacitors and one high-Q resonance capacitor.

[0040] In the embodiment, specifically, each low-frequency resonance circuit includes DC blocking capacitors C57 and C58, voltage dividing resistors R77 and R78, diodes D21 and D22, and resonance capacitor C77.

[0041] The voltage dividing resistor R77 is connected in parallel with the diode D21, and the voltage dividing resistor R78 is connected in parallel with the diode D22. The cathode of the diode D21 and the anode of the diode D22 are connected to the resonance capacitor C77. The anode of the diode D21 is connected to the DC blocking capacitor C57 and then grounded, and the cathode of the diode D22 is connected to the DC blocking capacitor C58 and then grounded. The cathode of the diode D22 is connected to the emitter of the triode Q1 and the collector of the triode Q4. The resistance values of the voltage dividing resistors R77 and R78 are the same.

[0042] In the embodiment, the voltage applied to the cathode of the diode D22 is DO1. When DO1 is +100V, the voltage at the anode of the diode D22 is +50V after voltage division by the voltage dividing resistors R77 and R78. It can be seen that the reverse bias voltage of the two diodes D21 and D22 is about +50V at this time.

[0043] In the embodiment, the high-frequency band of the high-frequency resonance circuit is 1300-1950MHz, and each high-frequency resonance circuit includes one PIN diode, one DC blocking capacitor, one high-frequency inductor and one high-Q resonance capacitor. Specifically, the high-frequency resonance circuit includes diode VD1, DC blocking capacitor C5, resonance capacitor C15 and high-frequency inductor L3. One end of the high-frequency inductor L3 is connected to the power supply, the other end is connected to the anode of the diode VD1 and the resonance capacitor C15, the cathode of the diode VD1 is connected to the DC blocking capacitor C5 and then grounded. The cathode of the diode VD1 is connected to the emitter of the triode Q1 and the collector of the triode Q4.

[0044] In the embodiment, +3.3V is applied to the anode of diode VD1 through high-frequency inductor L3, and the voltage applied to the cathode of diode VD1 is DO1. When DO1 is +100V, the reverse-bias off voltage drop borne by diode VD1 is about +97V, which is twice as large as the reverse-bias voltage drop borne by the PIN tube in the low-frequency band.

[0045] Please refer to Figures 1 to 4 As shown in the figure, in an embodiment of the utility model, when the frequency hopping filter works in the low-frequency band, the output pin of single-channel 2 input and gate chip U2 outputs low level, the collector and emitter of triode Q3 are not conductive, at this time the voltage VHB of product high-voltage network = +100V.

[0046] When the frequency hopping filter works in the high-frequency band, the output pin of chip U2 outputs high level, the collector and emitter of triode Q3 are conductive, one end of resistors R5 and R6 is short-circuited to the ground, and a voltage dividing circuit is formed with resistors R2 and R4, the resistance values of resistors R2, R4, R5 and R6 are the same, so at this time the voltage VHB of product high-voltage network = +50V, that is, when working in the high-frequency band, the reverse-bias off voltage applied to the PIN tube in the band is reduced from +100V to +50V, which greatly improves the reliability of the PIN tube, and also provides a wider selection space for reselecting the PIN tube in the band.

[0047] It is obvious for those skilled in the art that the utility model is not limited to the details of the above-mentioned exemplary embodiments, and can be realized in other specific forms without departing from the spirit or basic characteristics of the utility model. Therefore, the embodiments should be regarded as exemplary and non-limiting from any point of view, the scope of the utility model is defined by the appended claims rather than the above description, and therefore all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the utility model, and any reference signs in the claims should not be regarded as limiting the involved claims.

[0048] The above-described embodiments only represent the implementation of the utility model, the protection scope of the utility model is not limited to the above-described embodiments, and for those skilled in the art, on the premise of not departing from the concept of the utility model, a number of modifications and improvements can be made, which all belong to the protection scope of the utility model.

Claims

1. An ultra-wideband low-power frequency hopping filter, characterized by, The high-voltage switching circuit comprises: a single-channel 2-input AND gate chip U2, capacitors C1 and C2, a transistor Q3, resistors R2, R4, R5, R6 and R9. The two ends of the resistor R9 are respectively connected with the output pin of the single-channel 2-input AND gate chip U2 and the base of the transistor Q3; the emitter of the transistor Q3 is grounded; one end of the resistor R5 and the resistor R6 connected in parallel is connected with the collector of the transistor Q3, and the other end is connected with a resonance circuit. One end of the resistor R2 and the resistor R4 connected in parallel is connected with the resonance circuit, and the other end is connected with the capacitor C1 and then grounded. One end of the capacitor C2 is connected with the power supply pin of the single-channel 2-input AND gate chip U2, and the other end is grounded. The resistors R2, R4, R5 and R6 have the same resistance value.

2. The ultra-wideband low power frequency hopping filter of claim 1, wherein, The input pin of the single-channel 2-input AND gate chip U2 is connected with a frequency band signal.

3. The ultra-wideband low power frequency hopping filter of claim 1, wherein, The frequency hopping filter comprises a single-channel driving circuit connected with the high-voltage switching circuit; the single-channel driving circuit comprises transistors Q1, Q2 and Q4, and resistors R1, R3, R7 and R8.

4. The ultra-wideband low power frequency hopping filter of claim 1, wherein, The resistor R1 and the resistor R3 are connected in series, and the series connection end of the resistor R1 and the resistor R3 is connected with the other end of the resistor R5 and the resistor R6 connected in parallel; the resistor R1 is further connected with the collector of the transistor Q1; the resistor R3 is further connected with the base of the transistor Q1 and the collector of the transistor Q2. One end of the resistor R7 is connected with the base of the transistor Q2, and the two ends of the resistor R8 are respectively connected with the other end of the resistor R7 and the base of the transistor Q4. The emitter of the transistor Q2 and the emitter of the transistor Q4 are grounded; the emitter of the transistor Q1 is connected with the collector of the transistor Q4, and is connected with a resonance circuit; the other end of the resistor R7 is connected with an input level signal. The resonance circuit comprises a low-frequency resonance circuit; the low-frequency resonance circuit comprises blocking capacitors C57 and C58, voltage dividing resistors R77 and R78, diodes D21 and D22, and a resonance capacitor C77.

5. The ultra-wideband, low power hopping filter of claim 4, wherein, The voltage dividing resistor R77 is connected with the diode D21 in parallel, and the voltage dividing resistor R78 is connected with the diode D22 in parallel. The cathode of the diode D21 and the anode of the diode D22 are both connected with the resonance capacitor C77. The anode of the diode D21 is connected with the blocking capacitor C57 and then grounded, and the cathode of the diode D22 is connected with the blocking capacitor C58 and then grounded. The cathode of the diode D22 is connected with the emitter of the transistor Q1 and the collector of the transistor Q4. The voltage dividing resistors R77 and R78 have the same resistance value.

6. The ultra-wideband, low power hopping filter of claim 1, wherein, The resonance circuit comprises a high-frequency resonance circuit; the high-frequency resonance circuit comprises a diode VD1, a blocking capacitor C5, a resonance capacitor C15 and a high-frequency inductor L3.

7. The ultra-wideband, low power hopping filter of claim 4, wherein, One end of the high-frequency inductor L3 is connected with a power supply, and the other end is connected with the anode of the diode VD1 and the resonance capacitor C15; the cathode of the diode VD1 is connected with the blocking capacitor C5 and then grounded. The cathode of the diode VD1 is connected with the emitter of the transistor Q1 and the collector of the transistor Q4. ​

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