阅读说明：本技术 星用半双工vdes系统多通道射频收发机 (Satellite half-duplex VDES system multi-channel radio frequency transceiver ) 是由 王文伟 汪雪峰 张喆 罗小成 刘明利 戴善江 王晨旭 朱立楠 李健 于 2019-11-18 设计创作，主要内容包括：本发明提供了一种星用半双工VDES系统多通道射频收发机,包括：环形器、收发天线、接收通道、发射通道、本振、晶振；环形器用于分离发射信号和接收信号；收发天线接收自由空间中电磁波信号,并通过环形器和接收通道将接收信号传输至接收机；以及将发射通道通过环形器发送的电磁波信号辐射至自由空间中；接收通道将接收信号进行放大处理,并下变频至中频信号；发射通道将发射信号进行放大处理,并上变频至射频信号；晶振产生基准参考频率,并通过倍频方式得到本振频率本振根据本振频率,为接收通道和发射通道提供变频参考信号。从而可以实现VDES系统的多通道扩展,有效提高星用半双工VDES系统的信号收发效率。(The invention provides a satellite half-duplex VDES system multi-channel radio frequency transceiver, which comprises: the device comprises a circulator, a receiving and transmitting antenna, a receiving channel, a transmitting channel, a local oscillator and a crystal oscillator; the circulator is used for separating the transmitting signal and the receiving signal; the receiving and transmitting antenna receives electromagnetic wave signals in free space and transmits the received signals to the receiver through the circulator and the receiving channel; radiating the electromagnetic wave signal sent by the transmitting channel through the circulator into a free space; the receiving channel amplifies the received signal and down-converts the amplified signal to an intermediate frequency signal; the transmitting channel amplifies the transmitting signal and up-converts the signal to a radio frequency signal; the crystal oscillator generates a reference frequency, and obtains a local oscillator frequency by a frequency doubling mode, and the local oscillator frequency provides a frequency conversion reference signal for the receiving channel and the transmitting channel according to the local oscillator frequency. Therefore, the multichannel expansion of the VDES system can be realized, and the signal transceiving efficiency of the satellite half-duplex VDES system is effectively improved.)

1. A satellite half-duplex VDES system multi-channel radio frequency transceiver, comprising: the device comprises a circulator, a receiving and transmitting antenna, a receiving channel, a transmitting channel, a local oscillator and a crystal oscillator; the receiving channel and the transmitting channel are connected through a circulator to form a transceiving channel; wherein:

a first port of the circulator is connected with the transmitting and receiving antenna, a second port of the circulator is connected with the receiving channel, and a third port of the circulator is connected with the transmitting channel; the circulator is used for separating a transmitting signal and a receiving signal;

the receiving and transmitting antenna is used for receiving electromagnetic wave signals in free space and transmitting the received signals to a receiver through the circulator and the receiving channel; radiating the electromagnetic wave signal sent by the transmitting channel through the circulator into a free space;

the receiving channel is used for amplifying the received signal and performing down-conversion to an intermediate frequency signal;

the transmitting channel is used for amplifying the transmitting signal and up-converting the transmitting signal to a radio frequency signal;

the crystal oscillator is used for generating a reference frequency and obtaining a local oscillator frequency in a frequency doubling mode; the frequency doubling mode comprises the following steps: triple frequency of the transistor;

and the local oscillator is used for providing frequency conversion reference signals for the receiving channel and the transmitting channel according to the local oscillator frequency.

2. The satellite-use half-duplex VDES system multi-channel radio frequency transceiver of claim 1, comprising: the satellite half-duplex VDES system comprises two or more than two transceiving channels, wherein each transceiving channel is independent, and the working frequency of the satellite half-duplex VDES system is in the range of 150MHz to 165 MHz.

3. The satellite-use half-duplex VDES system multi-channel radio frequency transceiver of claim 2, wherein each of the transceiving channels is connected to a respective one of the transceiving antennas.

4. The satellite-use half-duplex VDES system multi-channel radio frequency transceiver of claim 2, wherein the transceiving channel is further provided with a receiver and a transmitter; the receiver is in a superheterodyne down-conversion mode, and the VHF signal is down-converted to the intermediate frequency through one-time frequency conversion; the transmitter is in a superheterodyne up-conversion mode, and up-converts the baseband signal to the VHF signal through one-time frequency conversion.

5. The multi-channel rf transceiver of a satellite half-duplex VDES system according to claim 2, wherein the baseband signal input of the transmitter employs a crystal filter to filter the input baseband signal.

6. The multi-channel RF transceiver of a satellite half-duplex VDES system of claim 2, wherein all the transmit/receive channels use the same local oscillator frequency.

7. The multi-channel radio frequency transceiver of the satellite half-duplex VDES system according to claim 2, wherein when the multi-channel radio frequency transceiver includes N transceiving channels, the multi-channel radio frequency transceiver further includes N equipower dividers, after the local oscillation frequency signal generated by the local oscillation is amplified, the N equipower dividers perform N equipower dividers, the N equipower dividers perform respective amplification processing, and the N2 equipower dividers obtain 2N local oscillation signals, and the 2N local oscillation signals are used as frequency conversion reference signals of each receiving channel and each transmitting channel of the N transceiving channels; wherein N is a natural number greater than 2.

8. The satellite-use half-duplex VDES system multichannel radio frequency transceiver of claim 7, wherein the N-way equipower splitter is composed of N-1 2 equipower splitters, and the 2 equipower splitters are T-shaped three-port networks composed of three 18 ohm resistors.

9. The satellite-use half-duplex VDES system multi-channel radio frequency transceiver of any one of claims 1 to 8, wherein the receive channel comprises a low noise amplifier, a first radio frequency filter, a first mixer, a first intermediate frequency amplifier, a first intermediate frequency filter, a second intermediate frequency amplifier, a receiver, connected in sequence;

the transmitting channel comprises a power amplifier, a second radio frequency filter, a radio frequency amplifier, a second mixer, a third intermediate frequency amplifier, a second intermediate frequency filter and a transmitter which are connected in sequence.

Technical Field

The invention relates to the technical field of communication, in particular to a satellite half-duplex VDES system multi-channel radio frequency transceiver.

Background

At present, the international maritime affairs mainly use the VHF frequency band, and according to the relevant regulation in radio regulation modified by the International telecommunication Union, the receiving and transmitting frequency range used by the satellite in the very high frequency Data Exchange System (VDES) is 150 MHz-165 MHz. Considering that the receiving and transmitting frequency is very close, the receiving and transmitting use a common antenna, and the transmitting power is large, most international satellite equipment communicates with ships and shore stations in a half-duplex mode, namely, a receiver and a transmitter in a VDES system on a satellite do not work simultaneously.

In the VDES system, the time slot conflict is a technical problem that needs to be solved with emphasis. Because the satellite beam coverage is very wide, the number of received ships is large, a lot of signals can be received at the same time, and a satellite receiver cannot demodulate a plurality of signals at the same time, so that time slot conflict is caused. To resolve the slot conflict, the method of narrowing the beam width range of the antenna, increasing the beam scanning time and increasing the number of channels can be used for resolution. Narrowing the antenna beam width range can reduce the number of received signals, but can affect the communication capacity; increasing the beam scanning time may increase the decision time of the target, but may increase software resources; the number of channels is increased, and the design of multiple channels is adopted, so that the communication capacity can be increased, and the time slot conflict solving capability is improved.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a satellite half-duplex VDES system multi-channel radio frequency transceiver.

The invention provides a multi-channel radio frequency transceiver of a satellite half-duplex VDES system, which comprises: the device comprises a circulator, a receiving and transmitting antenna, a receiving channel, a transmitting channel, a local oscillator and a crystal oscillator; the receiving channel and the transmitting channel are connected through a circulator to form a transceiving channel; wherein:

a first port of the circulator is connected with the transmitting and receiving antenna, a second port of the circulator is connected with the receiving channel, and a third port of the circulator is connected with the transmitting channel; the circulator is used for separating a transmitting signal and a receiving signal;

the receiving and transmitting antenna is used for receiving electromagnetic wave signals in free space and transmitting the received signals to a receiver through the circulator and the receiving channel; radiating the electromagnetic wave signal sent by the transmitting channel through the circulator into a free space;

the receiving channel is used for amplifying the received signal and performing down-conversion to an intermediate frequency signal;

the transmitting channel is used for amplifying the transmitting signal and up-converting the transmitting signal to a radio frequency signal;

the crystal oscillator is used for generating a reference frequency and obtaining a local oscillator frequency in a frequency doubling mode; the frequency doubling mode comprises the following steps: triple frequency of the transistor;

and the local oscillator is used for providing frequency conversion reference signals for the receiving channel and the transmitting channel according to the local oscillator frequency.

Optionally, comprising: the satellite half-duplex VDES system comprises two or more than two transceiving channels, wherein each transceiving channel is independent, and the working frequency of the satellite half-duplex VDES system is in the range of 150MHz to 165 MHz.

Optionally, each of the transceiving channels is connected to one of the transceiving antennas.

Optionally, the transceiving channel is further provided with a receiver and a transmitter; the receiver is in a superheterodyne down-conversion mode, and the VHF signal is down-converted to the intermediate frequency through one-time frequency conversion; the transmitter is in a superheterodyne up-conversion mode, and up-converts the baseband signal to the VHF signal through one-time frequency conversion.

Optionally, a baseband signal input end of the transmitter performs filtering processing on an input baseband signal by using a crystal filter.

Optionally, all the transceiving channels use the same local oscillation frequency.

Optionally, when the multi-channel radio frequency transceiver includes N transceiver channels, the multi-channel radio frequency transceiver further includes N equal power dividers, after a local oscillation frequency signal generated by the local oscillation is amplified, the N equal power dividers perform N equal power dividers, the N equal power dividers perform amplification processing respectively, and obtain 2N local oscillation signals through N2 equal power dividers, and the 2N local oscillation signals are used as frequency conversion reference signals of each receiving channel and each transmitting channel in the N transceiver channels; wherein N is a natural number greater than 2.

Optionally, the N-way power divider is composed of N-1 2 power dividers, and each 2 power divider is a T-shaped three-port network composed of three 18-ohm resistors.

Optionally, the receiving channel includes a low noise amplifier, a first radio frequency filter, a first mixer, a first intermediate frequency amplifier, a first intermediate frequency filter, a second intermediate frequency amplifier, and a receiver, which are connected in sequence;

the transmitting channel comprises a power amplifier, a second radio frequency filter, a radio frequency amplifier, a second mixer, a third intermediate frequency amplifier, a second intermediate frequency filter and a transmitter which are connected in sequence.

Compared with the prior art, the invention has the following beneficial effects:

according to the multi-channel radio frequency transceiver of the satellite half-duplex VDES system, each receiver and each transmitter are in a superheterodyne mode, the receiver obtains a required intermediate frequency signal through one-time frequency conversion, the transmitter obtains a required transmitting signal through one-time frequency conversion, and the transmitting and receiving local oscillator signals of each channel are shared, so that multi-channel expansion of the VDES system can be realized, the signal transmitting and receiving efficiency of the satellite half-duplex VDES system is effectively improved, the hardware scale can be greatly reduced, and the cost is reduced.

Drawings

Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:

fig. 1 is a schematic block diagram of a multi-channel rf transceiver of a satellite half-duplex VDES system according to the present invention;

fig. 2 is a schematic structural diagram of a 2-level power divider according to the present invention.

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that it would be obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit of the invention. All falling within the scope of the present invention.

Fig. 1 is a schematic block diagram of a multi-channel rf transceiver of a satellite half-duplex VDES system according to the present invention; as shown in fig. 1, the radio frequency transceiver includes a plurality of channels, each of which is designed identically and includes a circulator, a receiver and a transmitter, the receiver includes a low noise amplifier, a radio frequency filter, a mixer, an intermediate frequency amplifier, and the like, the transmitter includes an intermediate frequency filter, an amplifier, a mixer, and the like, the receiver and the transmitter share a local oscillation signal, and the local oscillation signal of each channel is generated after being amplified by a multi-stage power divider. The circulator is a three-port device and is used for connecting a transmitting signal and a receiving signal with an antenna. The amplifier is used for amplifying the signal, and a plurality of amplifiers are arranged in the channel, wherein the low-noise amplifier has the characteristic of low noise coefficient. The filter is used for filtering out-of-band signals. The power divider is used for dividing the local oscillator signal into two paths for output, and a plurality of power dividers are cascaded in the paths for use to obtain a plurality of paths of local oscillator signals. The crystal oscillator is used for generating a local oscillator reference frequency, for example, the local oscillator frequency is obtained by a frequency multiplication method.

Referring to fig. 1, each receiving channel includes a low noise amplifier, a first radio frequency filter, a first mixer, a first intermediate frequency amplifier, a first intermediate frequency filter, a second intermediate frequency amplifier, and a receiver, which are connected in sequence; each transmitting channel comprises a power amplifier, a second radio frequency filter, a radio frequency amplifier, a second mixer, a third intermediate frequency amplifier, a second intermediate frequency filter and a transmitter which are connected in sequence. Wherein, each receiving and transmitting channel is independent, and the working frequency of the satellite half-duplex VDES system is in the range of 150MHz to 165 MHz. Each transceiving channel is connected with a transceiving antenna respectively. The transceiving channel is also provided with a receiver and a transmitter; the receiver is in a superheterodyne down-conversion mode, and a VHF (Very High Frequency) signal is down-converted to an intermediate Frequency through one-time Frequency conversion; the transmitter is in a superheterodyne up-conversion mode, and the baseband signal is up-converted to the VHF signal through one-time frequency conversion.

In this embodiment, the circulator has three ports, each port has an isolation degree greater than 25dB, a standing wave of 1.2 at the port and an insertion loss of 0.5dB, and is configured to transmit a received signal to the duplexer of the receiving channel and transmit a transmit signal to the transmit-receive antenna. The low noise amplifier is used for carrying out first-stage amplification on the signal, the noise coefficient is smaller than 2dB, and the gain is 20 dB.

In this embodiment, the frequency mixer in the receiving channel is configured to perform down-conversion on the received signal, the frequency mixer in the transmitting channel is configured to perform up-conversion on the transmitted signal, and the local oscillation frequency is 150 MHz. If the radio frequency channel comprises N receiving and transmitting channels, the whole radio frequency channel needs 2N local oscillation signals.

In this embodiment, the input end of the transmitter uses the crystal filter to filter the input baseband signal, so as to improve the stray and phase noise indexes of the transmitter. The bandwidth of the crystal filter is selected as the bandwidth of the baseband signal, and the range is generally selected to be 100 kHz-200 kHz.

In this embodiment, the crystal oscillator is a temperature compensated crystal oscillator, and the output frequency is 50 MHz. And realizing triple frequency by a triode common-emitter circuit to obtain a 150MHz local oscillator signal.

Specifically, for example, with 8 transmit-receive channels, the local oscillator signal passes through an amplifier and then is input into a two-power-division network composed of resistors, and passes through 7 two-power-division networks to obtain 8 local oscillator signals. And 8 local oscillation signals are respectively input into 8 amplifiers for amplitude amplification, and then are subjected to 8 two-power division networks to obtain 16 local oscillation signals.

The design method adopted in the embodiment can realize 8 completely independent receiving and transmitting channels, and because the local oscillator signals are shared and the power divider is formed by adopting resistors, the system scale and the cost can be greatly reduced. The difficulty of channel design can be reduced by a one-time frequency conversion method. The crystal filter is designed at the input end of the transmitter, so that the stray and phase noise of the output signal of the transmitter can be greatly improved.

Fig. 2 is a schematic structural diagram of a 2-level power divider according to the present invention, and as shown in fig. 2, the 2-level power divider is a T-shaped three-port network formed by three 18-ohm resistors, and is configured to implement 2-level division of a local oscillator signal.

It should be noted that the embodiment does not limit the specific implementation form and the number of the 2 equal power dividers. When the multi-channel radio frequency transceiver comprises N receiving and transmitting channels, the multi-channel radio frequency transceiver further comprises N paths of equal power dividers, after local oscillation frequency signals generated by local oscillations are amplified, N paths of equal power dividers are used for carrying out N paths of equal power division, N paths of equal power division signals are respectively amplified, 2N paths of local oscillation signals are obtained through N2 paths of equal power dividers, and the 2N paths of local oscillation signals are used as frequency conversion reference signals of each receiving channel and each transmitting channel in the N receiving and transmitting channels; wherein N is a natural number greater than 2.

The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes or modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The embodiments and features of the embodiments of the present application may be combined with each other arbitrarily without conflict.