WO2007065328A1

WO2007065328A1 - A rf optical transmit device and a control method

Info

Publication number: WO2007065328A1
Application number: PCT/CN2006/001955
Authority: WO
Inventors: Sheng Liu; Wangsheng Fan; Chunhua Yang
Original assignee: Wuhan Winningchina Microsystem Technologies Co., Ltd.
Priority date: 2005-12-08
Filing date: 2006-08-03
Publication date: 2007-06-14
Also published as: CN1980097A

Abstract

A RF optical transmit device includes: RF/optical convert unit, optical / RF convert unit, RF attenuator, frequency shift keying unit, the device also includes: internet management unit, RF power collection unit, optical power collection unit, optical power control unit. A RF optical transmit control method is provided in the present invention, whose character in that: the method includes, the RF power collection unit collects the RF power of the RF input/output, generates the RF power signal; transmits the RF power signal to the RF power control unit, and computes difference value between RF power signal and the predetermined RF power value in the RF power control unit; the RF power control unit transmits the RF power control signal according to the difference value between RF power signal and the predetermined RF power value, and control automatically the power of the RF output signal and monitors the device.

Description

Radio frequency optical transmission equipment and control method

Technical field

The present invention relates to a signal transmission technology, and in particular to a radio frequency optical transmission device and a control method.

Background technique

In the existing technology, radio frequency optical transmission equipment includes a radio frequency/optical input unit and an optical/radio frequency output unit, where the radio frequency/optical input unit consists of a radio frequency input matching circuit, a high-pass filter circuit, a drive circuit, a laser, a low-pass filter circuit and an FSK Modulation circuit composition. The RF signal is sent to the drive circuit through the RF input matching circuit and the high-pass filter circuit. The control signal output by the FSK modulation circuit and the low-pass filter circuit is also output to the drive circuit, thereby converting the RF signal into an optical signal and outputting it through the optical fiber.

The optical/radio frequency output unit is composed of an optical/electrical converter, a matching amplifier circuit, a high-pass filter circuit, a variable attenuator, an output amplifier circuit, a low-pass filter circuit and an FSK demodulation circuit. The optical signal is converted into an electrical signal through an optical/electrical converter, and the electrical signal is amplified through a matching amplifier circuit to increase the signal gain. Then through the low-pass filter circuit and the high-pass filter circuit, the FSK modulated signal and the radio frequency signal are obtained respectively. The FSK modulated signal passes through the FSK demodulation circuit to obtain the demodulated signal. The RF signal passes through the adjustable attenuator and the output amplifier circuit to output the RF signal.

The technical solutions of the existing technology are mainly as follows: The radio frequency gain cannot be automatically controlled. The adjustment of the variable attenuator is mainly set manually by the manufacturer according to the user's needs before leaving the factory. Once installed, the user cannot adjust it according to the user's needs at different stages. And since it is manually set, its adjustment accuracy cannot be guaranteed.

Moreover, the existing technology cannot monitor the operating status of each component in the radio frequency optical equipment, which brings inconvenience to the maintenance of the system.

Contents of the invention

The present invention is aimed at the shortcomings in the existing technology of being unable to monitor the operating status of the equipment, having low integration level, and being unable to automatically control the radio frequency gain and radio frequency level, and provides an intelligent radio frequency optical transmission equipment.

The radio frequency optical transmission equipment provided by the present invention includes a radio frequency/optical conversion unit, an optical/radio frequency conversion unit, and a radio frequency attenuator. The equipment also includes: a radio frequency power collection unit, and the radio frequency light The radio frequency input and output terminals of the transmission equipment are connected to receive the radio frequency input and output power of the radio frequency optical transmission equipment and generate radio frequency power signals; the radio frequency power control unit is connected to the radio frequency power acquisition unit and is used to collect the radio frequency power according to the collected radio frequency power. The difference between the signal and the RF power set value is used to output the RF power control signal to the RF attenuator to realize the automatic control (ALC) function of the final output RF power.

Preferably, the radio frequency optical transmission device further includes: an optical power collection unit, connected to the output end of the radio frequency/optical conversion unit of the radio frequency optical transmission equipment, for collecting the optical power output by the radio frequency/optical conversion unit and generating light. Power signal; the optical power control unit is connected to the optical power acquisition unit and is used to output an optical power control signal to the optical path drive unit based on the difference between the collected optical power signal and the optical power setting value.

The present invention also provides a radio frequency optical transmission control method. The method includes: collecting radio frequency power at the radio frequency input and output ends through a radio frequency power acquisition unit, and generating a radio frequency power signal; sending the radio frequency power signal to the radio frequency power control unit; Calculate the difference between the radio frequency power signal and the radio frequency power setting value in the radio frequency power control unit; according to the difference between the radio frequency power signal and the radio frequency power setting value, the radio frequency power control unit outputs a radio frequency power control signal.

The present invention also provides a method for monitoring radio frequency optical transmission equipment. The method includes: collecting the input and output power of the radio frequency output terminal through a radio frequency power acquisition unit, and generating a radio frequency power signal; sending the radio frequency power signal to the radio frequency power control Unit; calculates the difference between the radio frequency power signal and the radio frequency power set value in the radio frequency power control unit; if the radio frequency power signal continues to be greater than the radio frequency power set value within a predetermined time, an alarm signal is generated through the radio frequency power control unit.

Preferably, the method further includes sending the alarm and status information generated by the radio frequency light control unit to the network management center through the network management unit to achieve remote control.

Utilizing the method provided by the present invention includes: collecting the radio frequency power at the radio frequency input end through the radio frequency power acquisition unit to generate a radio frequency power signal; sending the radio frequency power signal to the radio frequency power control unit; and comparing the radio frequency power signal with the radio frequency power in the radio frequency power control unit. The difference between the radio frequency power setting value; According to the difference between the radio frequency power signal and the radio frequency power setting value, the radio frequency power control unit outputs the radio frequency power control signal to realize the automatic level control (ALC) function. Collect and receive optical power through the optical power acquisition unit to generate an optical power signal; send the optical power signal to the optical power The rate control unit compares the difference between the optical power signal and the optical power setting value in the optical power control unit; and calculates the optical power control unit output gain control signal based on the difference between the optical power signal and the optical power setting value.

The radio frequency optical transmission equipment and control method of the present invention are used to collect and analyze the performance and status (for example, luminous power, light receiving power, radio frequency power, etc.) of the radio frequency optical transmission equipment, and can intelligently adjust the radio frequency output power of the equipment , to keep it in optimal working condition.

In addition, since the control unit is integrated with the traditional radio frequency optical transmission module, the integration level of the system is improved. Due to the monitoring of the radio frequency signal output power and optical power, the laser and radio frequency output device of the radio frequency optical transmission equipment can be monitored. By analyzing, judging and monitoring the working conditions and device performance, we can better maintain RF optical transmission equipment.

Description of the drawings

Figure 1 is a system structure diagram of an embodiment of the radio frequency optical transmission device according to the present invention.

Figure 2 is a schematic circuit diagram of an embodiment of the radio frequency optical transmission device according to the present invention.

Figure 3 is a flow chart of an embodiment of the monitoring method for radio frequency optical transmission equipment according to the present invention. Detailed ways

First of all, it should be pointed out that the meanings of the terms, words and claims used in the present invention cannot be limited to their literal and ordinary meanings, but also include meanings and concepts that are consistent with the technology of the present invention. This is Because we, as inventors, need to properly define terms to best describe our inventions. Therefore, the configurations given in the description and drawings are only preferred embodiments of the present invention, and are not intended to enumerate all technical characteristics of the present invention. We need to realize that there are a variety of equivalents or modifications that can replace our plans

Figure 1 is a system structure diagram of an embodiment of the radio frequency optical transmission device according to the present invention. The radio frequency optical transmission equipment provided by the present invention includes a radio frequency/optical conversion unit, an optical/radio frequency conversion unit, a radio frequency attenuator, a frequency shift keying unit, a low noise amplification unit, and a power amplification unit. The equipment also includes: radio frequency power collection Unit, RF power control unit, low noise amplifier, power amplifier. The system also includes: an optical power collection unit, an optical power control unit and an automatic level controller (ie, ALC controller).

The radio frequency power collection unit is connected to the radio frequency input and output ends of the radio frequency optical transmission device. That is, it is connected to the input and output terminals of the radio frequency optical transmission equipment to collect the input and output of the radio frequency optical transmission equipment. The radio frequency signal at the output port is sampled by the power collection circuit in the radio frequency power collection unit, and then the obtained electrical signal is converted into a digital signal by the analog-to-digital conversion circuit. The digital signal generated is the radio frequency power signal.

The radio frequency power control unit is connected to the radio frequency power acquisition unit. First, receive the radio frequency power signal generated by the radio frequency power acquisition unit. The radio frequency power control unit also stores a preset radio frequency power signal reference value. The radio frequency power signal setting value can be set by the operator through the human-machine interface with the microcontroller or other hardware logic unit as the radio frequency power control unit. Make settings. Compare the collected RF power signal and the RF power signal setting value, that is, find the difference between the two. Based on the difference, the radio frequency power control unit outputs a radio frequency power control signal to the radio frequency attenuator. In the embodiment of the present invention, preferably, there is a proportional relationship between the control signal and the difference. For example, the proportional coefficient is 2, and when the difference is 0.2V (that is, the collected radio frequency power signal is higher than the radio frequency When the power signal setting value is 0.2V), a 0.4V RF power control signal is generated. The RF power control signal is output to the RF attenuator through the communication port of the RF power control unit.

The optical power collection unit is connected to the laser output end and the optical fiber input end of the radio frequency optical transmission equipment. The optical power collection unit includes a PIN photoelectric conversion device, which is used to receive the optical power from the laser output end or the optical fiber input end and generate an optical power signal.

The optical power control unit is connected to the optical power collection unit and is used to output an optical power control signal to the optical/radio frequency conversion unit according to the difference between the collected optical power signal and the optical power setting value to control the output of the laser.

Preferably, the above-mentioned optical power control unit can also be connected to the radio frequency power control unit to provide the optical power control signal to the radio frequency power control unit. The radio frequency power control unit also generates a radio frequency power control signal according to the optical power control signal. Refer to Figure 2. The radio frequency power control signal controls another level of digitally controlled attenuator 15. Thus, the radio frequency control gain of the radio frequency power control unit can be increased.

The ALC controller is used to generate a radio frequency power control signal according to the set value in the device and the radio frequency power value collected by the radio frequency power acquisition unit, and adjust the radio frequency input value at the input end of the radio frequency attenuator. The ALC controller can be implemented through a commonly used ALC control circuit.

Figure 2 is a schematic circuit diagram of an embodiment of the radio frequency optical transmission device according to the present invention. at In the above embodiment:

The RF/optical conversion unit includes a RF input matching circuit 1, a filter circuit 2, a drive circuit 3, a laser 4, and preferably includes a low-pass filter 6 and an FSK modulator 5. The radio frequency signal is received by the antenna, and is sent to the laser 4 through input matching 1 and filtering 2, and is converted into an optical signal. At the same time, the monitored data stream is also sent to the laser 4 through FSK modulation 5 and low-pass filtering 6, and is converted into an optical signal and sent out. .

The optical/radio frequency conversion unit includes a PIN/photoelectric conversion circuit 9 (PIN photoelectric tube), a matching amplifier circuit 10, a filter circuit 13, three-stage radio frequency amplifier circuits 14, 16, 19, and an impedance matching circuit 18, and preferably includes Low-pass filter circuit 11 and FSK demodulation circuit 12. The optical signal coming from the optical fiber is multiplexed by WDM (Wavelength Division Multiplexer) 7, and then converted into an electrical signal through photoelectric conversion 9. After matching and amplification 10, it undergoes three-level radio frequency amplification 14, 16, 19 and two-level numerically controlled attenuation. After 15 and 17, it is sent out by the radio frequency antenna, and at the same time sent to the low-pass filter circuit 11 to filter out the low-frequency signal and sent to the FSK demodulator 12 to obtain the monitoring information sent by the opposite end. Between each two-stage radio frequency amplification circuit, two-stage digitally controlled attenuators 15 and 17 are inserted.

The radio frequency power collection unit includes an integrated power circuit and an analog/digital conversion circuit. The optical power collection circuit 23 and the radio frequency signal power collection circuit 25 adopt an integrated power chip, such as AD8362, or a PIN photoelectric conversion circuit, such as PDCS983. The A/D converters 24 and 26 adopt A/D conversion chips, such as TLC1543.

The optical power control unit 22 adopts a single chip microcomputer, such as an 8031 single chip microcomputer. The light receiving power signal is collected through the optical power acquisition circuit 23, and after A/D conversion 24, it is input to the radio frequency power control unit 22, and compared with the light receiving power value set by the system, and the radio frequency is determined based on the obtained difference. The attenuation value of the attenuator 15 is used to control the changes in the optical path; the output radio frequency signal power is collected through the radio frequency power acquisition circuit 25, converted by the A/D converter 26 and sent to the radio frequency power control unit 22 and the set power. The set values are compared, and the attenuation value of the numerically controlled attenuator 17 is determined and controlled based on the obtained difference, thereby achieving stability of the output radio frequency power. The RF attenuator uses HM274 RF chip. The input RF signal power is collected through the RF power acquisition circuit 25 and sent to the ALC control unit 30 for comparison with the value set by the module control unit 22, and the attenuation value 31 of the voltage-controlled attenuator is dynamically adjusted to achieve automatic input level control. In this embodiment, a network management unit is also included, which is used to send signals from the radio frequency power control unit or optical power control unit to the network management center and send setting values from the network management center to the radio frequency power control unit or optical power control unit, so as to Realize remote control of equipment. The network management unit 29 includes an RS232 transceiver chip and an RS485 transceiver chip, wherein the RS232 transceiver chip is MAX232, and the RS485 transceiver chip is MAX1487E.

Between the device and the network management unit in this embodiment, the command packet adopts a complete frame structure to ensure correct transmission. The frame structure of a complete command package is as follows:

Start flag unit: 1 byte in length, indicating the beginning of a complete command package, fixed to hexadecimal number 0X7E.

Fixed word: 1 byte length, used for module identification, fixed to hexadecimal number 0X06.

Module address: 1 byte in length, used to identify multiple radio frequency optical transmission devices in the same network. The address of each device in the network is unique. Each device only parses commands whose module address is equal to its own address.

Command number: 1 byte length, unique identifier of the command. The command number in the response command is the same as the command number of the received command.

Reserved bits: 1 byte length, set to 0x00. (This can be used as a response handshake mark if needed)

Command body length: 1 byte length, the actual length of the command data, in bytes. Command data: variable length, the actual command information required for this command.

Reserved unit: 2 bytes, reserved (if necessary, here is the CRC16 check digit).

End flag unit: 1 byte length, indicating the end of a complete command package, fixed to hexadecimal number 0X7F. In order to prevent the end of the previous frame from being confused with the beginning of the next frame, the start flag and the end flag are distinguished.

The communication method used between the radio frequency optical transmission equipment and the network management unit can be synchronous (or asynchronous) full-duplex (or half-duplex) communication, 8 data bits, 1 stop bit, no parity bit, The rate is 19200BPS (or other baud rate). The sign bit of the signed number during the transmission process uniformly adopts the complement representation. The network management center or radio frequency optical transmission equipment preferably performs authentication processing after receiving the data packet. The authentication processing includes: start flag/end flag verification, command number verification, and command data length verification. If any of the above steps fails to pass the verification, it will be considered In case of authentication failure, the receiver should respond with an error flag to the sender according to the actual situation.

In this embodiment, a low noise amplifier (LNA) and a power amplifier (PAA) are also included.

Figure 3 is a flow chart of an embodiment of the radio frequency optical transmission equipment monitoring method according to the present invention. After system startup:

In step 110, the output power of the radio frequency output terminal is collected through the radio frequency power acquisition unit to generate a radio frequency power signal.

At step 120, the radio frequency power signal is sent to the radio frequency power control unit.

In step 130, the difference between the radio frequency power signal and the radio frequency power setting value in the radio frequency power control unit is calculated.

In step 140, determine whether the RF power signal is less than the RF power setting value. If the radio frequency power signal is less than the radio frequency power set value, in step 170, the radio frequency power control unit outputs an enhanced signal to the radio frequency attenuator, and in step 180, starts timing. In step 190, if within the predetermined time, the radio frequency power signal continues to be less than If the radio frequency power setting value is greater than the radio frequency power setting value, an alarm signal is generated by the radio frequency power control unit. If within a predetermined time, the radio frequency power signal is greater than the radio frequency power setting value, then return to step 140; if the radio frequency power signal is greater than the radio frequency power setting value, then In step 150, the radio frequency power control unit outputs an attenuation signal to the radio frequency attenuator, and in step 160, the timer is cleared.

It should be pointed out that the implementation of the present invention is not limited to the above-mentioned embodiments. If there are other forms of modifications, they will also fall within the protection scope of the present invention as long as they do not deviate from the spirit and essence of the present invention.

Claims

Rights request

1. A radio frequency optical transmission device, including a radio frequency/optical conversion unit, an optical/radio frequency conversion unit and a radio frequency attenuator, a frequency shift keying unit, a low noise amplification unit, and a power amplification unit, characterized in that the equipment also includes -.

The network management unit is used to communicate with the network management center through the network port and according to the corresponding protocol; the radio frequency power collection unit is connected to the radio frequency input and output terminals of the radio frequency optical transmission equipment, and is used to receive the radio frequency input and output of the radio frequency optical transmission equipment. Output power and generate a radio frequency power signal; the radio frequency power control unit is connected to the radio frequency power acquisition unit and is used to output a radio frequency power control signal to the radio frequency attenuator according to the difference between the collected radio frequency power signal and the radio frequency power setting value;

The optical power collection unit is connected to the radio frequency/optical conversion unit and the light/radio frequency conversion unit of the radio frequency optical transmission equipment, and is used to collect the optical output power and optical input power of the radio frequency optical transmission equipment; the optical power control unit is connected to the optical power The acquisition unit is connected and used to output a radio frequency power control signal to the radio frequency attenuator according to the difference between the collected optical power signal and the optical power setting value.

2. The device according to claim 1, characterized in that, the radio frequency/optical conversion unit includes a matched filter circuit, a drive circuit and a laser; the optical/radio frequency conversion unit includes a photoelectric conversion circuit, a matched filter circuit and a radio frequency amplification circuit.

3. The device according to claim 1 or 2, characterized in that, the radio frequency/optical conversion unit includes a low-pass filter circuit and an FSK modulation circuit; the optical/radio frequency conversion unit includes a low-pass filter circuit and an FSK demodulation circuit. circuit.

4. The device according to claim 1, wherein the radio frequency power collection unit includes a radio frequency signal collector, an optical power collector and an analog/digital converter.

5. The device according to claim 1, characterized in that, the optical power control unit is connected to the optical power collection unit, and is used to control the optical power according to the difference between the collected optical power signal and the optical power setting value. The light attenuation automatic compensation control signal is output to the radio frequency power control unit according to the setting value of the device.

6. The device according to claim 5, characterized in that the optical power collection unit is connected to a radio frequency power control unit, and the radio frequency power control unit uses the optical power signal to generate a radio frequency power control signal.

7. The device according to claim 1, characterized in that the device integrates a low noise amplifier and a power amplifier.

8. A radio frequency optical transmission control method, characterized in that the method includes:

a. Collect the RF power at the RF input and output ends through the RF power acquisition unit to generate a RF power signal;

b. Send the radio frequency power signal to the radio frequency power control unit;

c Calculate the difference between the RF power signal and the RF power setting value in the RF power control unit;

d. Based on the difference between the radio frequency power signal and the radio frequency power set value, the radio frequency power control unit outputs a radio frequency power control signal.

9. The method according to claim 8, characterized in that, in step d, when the radio frequency power signal is greater than the radio frequency power set value, the radio frequency power control unit outputs an attenuation signal to the radio frequency attenuator; when the radio frequency power signal is less than When the radio frequency power is set to a value, the radio frequency power control unit outputs an enhanced signal to the radio frequency attenuator.

10. A method for monitoring radio frequency optical transmission equipment, characterized in that the method includes:

a. Collect the input and output power of the RF output terminal through the RF power collection unit to generate a RF power signal;

d. If within a predetermined time, the radio frequency power signal continues to be greater than the radio frequency power set value, an alarm signal is generated through the radio frequency power control unit.

11. The method according to claim 10, characterized in that, after step d, it includes sending the alarm signal generated by the radio frequency optical control unit and the collected optical power signal and radio frequency power signal of the module through the network management unit Go to the network management center to achieve remote control.