A shortwave pre-selector

Abstract

The invention belongs to the technical field of digital tuning frequency hopping communication, and discloses a shortwave pre-postselector with high frequency hopping speed, stable and reliable operation, and the shortwave pre-postselector with higher selectivity; the shortwave pre-postselector is arranged inside a shortwave radio station, and is provided with a preselector signal input terminal, a postselector signal input terminal, a preselector signal output terminal and a postselector signal output terminal; the shortwave pre-postselector comprises: a control unit, a limiting protection unit, a first transceiver conversion unit, a first band conversion unit, a first resonance unit, an amplification unit, a second resonance unit, a second band conversion unit and a second transceiver conversion unit.

Description

Technical Field

[0001] The invention belongs to the technical field of digital tuning frequency hopping communication, and in particular relates to a shortwave pre-selector. Background Art

[0002] With the continuous advancement of frequency hopping communication technology, pre-selectors have been recognized by more and more designers for their superior performance indicators and have been widely used in military and civilian communication systems. They present matching transmission for frequencies within the passband and reflection attenuation for frequency mismatches within the stopband, thereby realizing the signal spectrum filtering function.

[0003] For traditional shortwave pre-selectors and post-selectors, the pre-selector mostly adopts the mode of first amplification and then two-stage filtering, while the post-selector mostly adopts the mode of first two-stage filtering and then amplification. This mode of shortwave pre-selector and post-selector has a large dynamic range and good intermodulation indicators, but the selectivity is relatively poor. Summary of the invention

[0004] In view of the shortcomings of the above-mentioned technology, the present invention provides a shortwave pre-selector and post-selector with fast frequency hopping speed, stable and reliable operation, and capable of realizing a shortwave pre-selector with higher selectivity.

[0005] In order to achieve the above object, the present invention adopts the following technical solution to achieve it.

[0006] A shortwave pre-postselector, which is arranged inside a shortwave radio station, and is provided with a preselector signal input terminal, a postselector signal input terminal, a preselector signal output terminal and a postselector signal output terminal; the shortwave pre-postselector comprises: a control unit, a limiting protection unit, a first transceiver conversion unit, a first band conversion unit, a first resonance unit, an amplification unit, a second resonance unit, a second band conversion unit and a second transceiver conversion unit;

[0007] The control signal output end of the control unit is connected in parallel with the control signal input end of the first transceiver conversion unit, the control signal input end of the second transceiver conversion unit, the control signal input end of the first band conversion unit, the control signal input end of the second band conversion unit, the control signal input end of the first resonance unit and the control signal input end of the second resonance unit respectively;

[0008] The signal input end of the limiting protection unit serves as the preselector signal input end, and the signal output end of the limiting protection unit is connected to the first signal input end of the first transceiver conversion unit; the second signal input end of the first transceiver conversion unit serves as the postselector signal input end; the signal output end of the first transceiver conversion unit is connected to the signal input end of the first band conversion unit, the signal output end of the first band conversion unit is connected to the signal input end of the first resonance unit, the signal output end of the first resonance unit is connected to the signal input end of the amplifying unit, the signal output end of the amplifying unit is connected to the signal input end of the second resonance unit, the signal output end of the second resonance unit is connected to the signal input end of the second band conversion unit, the signal output end of the second band conversion unit is connected to the signal input end of the second transceiver conversion unit, the first signal output end of the second transceiver conversion unit serves as the preselector signal output end, and the second signal output end of the second transceiver conversion unit serves as the postselector signal output end.

[0009] The characteristics and further improvements of the technical solution of the present invention are:

[0010] (1) The control unit is used to receive a serial control instruction sent by a shortwave radio station main control unit, and convert the serial control instruction into a 16-bit parallel control code, wherein the control code bits 1 to 8 are used to set the resonant frequency generated by the first resonant unit and the second resonant unit; bits 9 and 10 are used to select the working band of the first band conversion unit and the second band conversion unit; bit 11 is used to control the transceiver working state of the first transceiver conversion unit and the second transceiver conversion unit; bits 12 to 16 are reserved bits;

[0011] When the 11th bit is 0, the first transceiver conversion unit and the second transceiver conversion unit respectively work in the receiving state, and when the 11th bit is 1, the first transceiver conversion unit and the second transceiver conversion unit respectively work in the sending state; or, when the 11th bit is 0, the first transceiver conversion unit and the second transceiver conversion unit respectively work in the sending state, and when the 11th bit is 1, the first transceiver conversion unit and the second transceiver conversion unit respectively work in the receiving state.

[0012] (2) The operating frequency range of the first band conversion unit and the second band conversion unit is 1.6 MHz-30 MHz, and the operating frequency range 1.6 MHz-30 MHz is divided into 1.6 MHz-3.999 MHz band, 4 MHz-9.999 MHz band, and 10 MHz-30 MHz band.

[0013] (3) The control unit is composed of two cascaded shift registers.

[0014] (4) The limiting protection unit is composed of two power PIN diodes connected in series.

[0015] (5) The first transceiver conversion unit and the second transceiver conversion unit respectively use a two-choice electronic switch.

[0016] (6) The first band conversion unit and the second band conversion unit respectively use a four-to-one electronic switch.

[0017] (7) The first resonant unit and the second resonant unit respectively adopt an integrated shortwave frequency hopping filter, and the operating frequency of the integrated shortwave frequency hopping filter is 1.6 MHz-30 MHz.

[0018] (8) The integrated shortwave frequency hopping filter is packaged using a shielding cover.

[0019] Compared with the existing technology, the present invention has the following advantages: the shortwave pre-selector of the present invention adopts a mode of first filtering, then amplifying and then filtering, and the bottom noise of the pre-selector is small and the selectivity is high; the control unit adopts a shift register, the control method is simple, and the frequency switching speed is fast. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 A schematic diagram of the structure of a shortwave pre-selector and post-selector provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] The embodiment of the present invention provides a shortwave pre-selector, such as Figure 1As shown, the shortwave pre-postselector is arranged inside the shortwave radio station, and the shortwave pre-postselector is provided with a preselector signal input terminal, a postselector signal input terminal, a preselector signal output terminal and a postselector signal output terminal; the shortwave pre-postselector comprises: a control unit, a limiting protection unit, a first transceiver conversion unit, a first band conversion unit, a first resonance unit, an amplification unit, a second resonance unit, a second band conversion unit and a second transceiver conversion unit;

[0024] The control signal output end of the control unit is connected in parallel with the control signal input end of the first transceiver conversion unit, the control signal input end of the second transceiver conversion unit, the control signal input end of the first band conversion unit, the control signal input end of the second band conversion unit, the control signal input end of the first resonance unit and the control signal input end of the second resonance unit respectively;

[0025] The signal input end of the limiting protection unit serves as the preselector signal input end, and the signal output end of the limiting protection unit is connected to the first signal input end of the first transceiver conversion unit; the second signal input end of the first transceiver conversion unit serves as the postselector signal input end; the signal output end of the first transceiver conversion unit is connected to the signal input end of the first band conversion unit, the signal output end of the first band conversion unit is connected to the signal input end of the first resonance unit, the signal output end of the first resonance unit is connected to the signal input end of the amplifying unit, the signal output end of the amplifying unit is connected to the signal input end of the second resonance unit, the signal output end of the second resonance unit is connected to the signal input end of the second band conversion unit, the signal output end of the second band conversion unit is connected to the signal input end of the second transceiver conversion unit, the first signal output end of the second transceiver conversion unit serves as the preselector signal output end, and the second signal output end of the second transceiver conversion unit serves as the postselector signal output end.

[0026] Specifically, the control unit is used to receive a serial control instruction sent by a shortwave radio station main control unit, and convert the serial control instruction into a 16-bit parallel control code, wherein the control code from the 1st to the 8th bit is used to set the resonant frequency generated by the first resonance unit and the second resonance unit; the 9th and 10th bits are used to select the working band of the first band conversion unit and the second band conversion unit; the 11th bit is used to control the transceiver working state of the first transceiver conversion unit and the second transceiver conversion unit; the 12th to the 16th bits are reserved bits;

[0027] When the 11th bit is 0, the first transceiver conversion unit and the second transceiver conversion unit respectively work in the receiving state, and when the 11th bit is 1, the first transceiver conversion unit and the second transceiver conversion unit respectively work in the sending state; or, when the 11th bit is 0, the first transceiver conversion unit and the second transceiver conversion unit respectively work in the sending state, and when the 11th bit is 1, the first transceiver conversion unit and the second transceiver conversion unit respectively work in the receiving state.

[0028] The amplitude limiting protection unit is used to limit the amplitude of the input signal of the preselector signal input terminal;

[0029] The first transceiver conversion unit and the second transceiver conversion unit are used to switch the preselector to receive signals or the postselector to send signals under the control of the control unit;

[0030] The first band conversion unit and the second band conversion unit are used to select corresponding working frequency bands under the control of the control unit;

[0031] The first resonance unit and the second resonance unit are used to generate corresponding resonance frequencies under the control of the control unit;

[0032] The amplifying unit amplifies the input signal.

[0033] Further, the operating frequency range of the first band conversion unit and the second band conversion unit is 1.6MHz-30MHz, and the operating frequency range 1.6MHz-30MHz is divided into 1.6MHz-3.999MHz band, 4MHz-9.999MHz band, and 10MHz-30MHz band.

[0034] Furthermore, the control unit is composed of two cascaded shift registers.

[0035] Exemplarily, the shift register adopts 74HC164D.

[0036] Furthermore, the amplitude limiting protection unit is composed of two power PIN diodes connected in series, and the amplitude limiting protection unit can withstand a radio frequency signal input power of 100W.

[0037] Furthermore, the first transceiver conversion unit and the second transceiver conversion unit are respectively implemented by a two-choice electronic switch. Exemplarily, when the 11th bit in the 16-bit parallel control code is at a low level, the post-selector works, and the first transceiver conversion unit and the second transceiver conversion unit work in a transmitting state; when the 11th bit in the 16-bit parallel control code is at a high level, the pre-selector works, and the first transceiver conversion unit and the second transceiver conversion unit work in a receiving state.

[0038] Furthermore, the first band conversion unit and the second band conversion unit are respectively implemented by a four-to-one electronic switch. Exemplarily, when the 9th and 10th bits in the 16-bit parallel control code are both low, the first band 1.6MHz to 3.999MHz works; when the 9th bit is low and the 10th bit is high, the second band 4MHz to 9.999MHz works; when the 9th bit is high and the 10th bit is low, the third band 10MHz to 30MHz works; when the 9th bit and the 10th bit are both high, the RF signal input terminal and the RF signal output terminal are directly connected.

[0039] Furthermore, the first resonance unit and the second resonance unit are respectively implemented by integrated shortwave frequency hopping filters, and the operating frequency of the integrated shortwave frequency hopping filters is 1.6 MHz-30 MHz.

[0040] Furthermore, the integrated shortwave frequency hopping filter is packaged with a shielding cover. Exemplarily, the shielding cover can be a metal outer cover.

[0041] The amplifying unit is implemented by an integrated broadband amplifier. The amplifying unit is applied between the first resonant unit and the second resonant unit. The useful radio frequency signal is first filtered by the first resonant unit, then amplified by the amplifying unit, and then output by the second resonant unit through frequency selection filtering.

[0042] The specific working process of the shortwave pre-selector of the present invention is as follows:

[0043] The main control unit of the shortwave radio station sends the required frequency signal to the shortwave pre-selector in a serial communication mode through a low-frequency interface. After receiving the serial clock and data instructions, the control unit of the present invention converts them into 16-bit parallel tuning codes A0-A15 (where A11-A15 are vacant arbitrary codes) through a shift register, A10 selects the transceiver channel, A8 and A9 select the band, and A0-A7 calls the data inside the resonance unit to generate a useful frequency signal.

[0044] When A10 is at a high level, the preselector works, and the RF signal is input from the preselector input terminal and first passes through the limiting protection unit. If the input signal amplitude is too large, the limiting protection unit performs limiting processing. If the input signal amplitude is normal, the limiting protection unit does not work.

[0045] After the RF input signal passes through the limiting protection unit, the receiving channel is selected by the first transceiver conversion unit, the working frequency band is selected by the first band conversion unit, the signal is filtered by the first resonance unit, the signal output amplitude is increased by the amplification unit, and then the signal is filtered twice by the second resonance unit, the working frequency band is selected by the second band conversion unit, and finally the receiving channel is selected by the second transceiver conversion unit and output to the output end of the preselector; when A10 is a low level, the post-selector works, and the RF signal is input from the input end of the post-selector, the transmitting channel is first selected by the first transceiver conversion unit, the working frequency band is selected by the first band conversion unit, the signal is filtered by the first resonance unit, the signal output amplitude is increased by the amplification unit, and then the signal is filtered twice by the second resonance unit, the working frequency band is selected by the second band conversion unit, and finally the transmitting channel is selected by the second transceiver conversion unit and output to the output end of the post-selector.

[0046] The shortwave pre-selector and post-selector of the present invention has a control unit using a shift register, the shift register has a fast conversion speed, and the frequency switching time of the shortwave pre-selector is less than 1ms; the amplification unit is arranged between the two-stage resonance units, the resonance unit can effectively filter out the noise and clutter caused by the radio frequency input signal, and the shortwave pre-selector has good selectivity.

[0047] After testing and actual use, the pre-selector of the present invention has fast frequency hopping speed, high selectivity, stable and reliable operation. After being applied to shortwave radio stations, the receiver sensitivity can be improved by 2dBm-3dBm, and the transmitter out-of-band suppression can be improved by 10dB, which can effectively improve the electromagnetic compatibility of shortwave radio stations.

[0048] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A shortwave pre-selector, characterized in that: The shortwave pre-postselector is arranged inside the shortwave radio station, and is provided with a preselector signal input terminal, a postselector signal input terminal, a preselector signal output terminal and a postselector signal output terminal; the shortwave pre-postselector comprises: a control unit, a limiting protection unit, a first transceiver conversion unit, a first band conversion unit, a first resonance unit, an amplification unit, a second resonance unit, a second band conversion unit and a second transceiver conversion unit; The control signal output end of the control unit is connected in parallel with the control signal input end of the first transceiver conversion unit, the control signal input end of the second transceiver conversion unit, the control signal input end of the first band conversion unit, the control signal input end of the second band conversion unit, the control signal input end of the first resonance unit and the control signal input end of the second resonance unit respectively; The signal input end of the amplitude limiting protection unit serves as the preselector signal input end, and the signal output end of the amplitude limiting protection unit is connected to the first signal input end of the first transceiver conversion unit; the second signal input end of the first transceiver conversion unit serves as the postselector signal input end; the signal output end of the first transceiver conversion unit is connected to the signal input end of the first band conversion unit, the signal output end of the first band conversion unit is connected to the signal input end of the first resonance unit, the signal output end of the first resonance unit is connected to the signal input end of the amplifying unit, the signal output end of the amplifying unit is connected to the signal input end of the second resonance unit, the signal output end of the second resonance unit is connected to the signal input end of the second band conversion unit, the signal output end of the second band conversion unit is connected to the signal input end of the second transceiver conversion unit, the first signal output end of the second transceiver conversion unit serves as the preselector signal output end, and the second signal output end of the second transceiver conversion unit serves as the postselector signal output end; The useful radio frequency signal output from the first band conversion unit is first filtered by the first resonance unit, then amplified by the amplification unit, and then output by the second resonance unit through frequency selection filtering; The control unit is composed of two shift registers cascaded; The first resonance unit and the second resonance unit respectively adopt an integrated shortwave frequency hopping filter, and the operating frequency of the integrated shortwave frequency hopping filter is 1.6MHz-30MHz; The amplitude limiting protection unit is composed of two power PIN diodes connected in series.

2. A shortwave pre-selector and post-selector according to claim 1, characterized in that: The control unit is used to receive the serial control instruction sent by the shortwave radio main control unit, and convert the serial control instruction into a 16-bit parallel control code, wherein the control code from the 1st to the 8th bit is used to set the resonance frequency generated by the first resonance unit and the second resonance unit; the 9th and 10th bits are used to select the working band of the first band conversion unit and the second band conversion unit; the 11th bit is used to control the transceiver working state of the first transceiver conversion unit and the second transceiver conversion unit; the 12th to the 16th bits are reserved bits; When the 11th bit is 0, the first transceiver conversion unit and the second transceiver conversion unit respectively work in the receiving state, and when the 11th bit is 1, the first transceiver conversion unit and the second transceiver conversion unit respectively work in the sending state; or, when the 11th bit is 0, the first transceiver conversion unit and the second transceiver conversion unit respectively work in the sending state, and when the 11th bit is 1, the first transceiver conversion unit and the second transceiver conversion unit respectively work in the receiving state.

3. A shortwave pre-selector and post-selector according to claim 2, characterized in that: The operating frequency range of the first band conversion unit and the second band conversion unit is 1.6 MHz-30 MHz, and the operating frequency range 1.6 MHz-30 MHz is divided into 1.6 MHz-3.999 MHz band, 4 MHz-9.999 MHz band, and 10 MHz-30 MHz band.

4. A shortwave pre-selector and post-selector according to claim 1, characterized in that: The first transceiver conversion unit and the second transceiver conversion unit respectively use a one-or-two electronic switch.

5. A shortwave pre-selector and post-selector according to claim 1, characterized in that: The first band conversion unit and the second band conversion unit respectively use a four-to-one electronic switch.

6. A shortwave pre-selector and post-selector according to claim 1, characterized in that: The integrated short-wave frequency-hopping filter is packaged by a shielding cover.

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