CN202364227U

CN202364227U - Optical receiving module

Info

Publication number: CN202364227U
Application number: CN201120530176XU
Authority: CN
Inventors: 刘勇刚
Original assignee: SHENZHEN SANLAND ELECTRONIC CO Ltd
Current assignee: SHENZHEN WANHE TECHNOLOGY CO., LTD.
Priority date: 2011-12-16
Filing date: 2011-12-16
Publication date: 2012-08-01
Anticipated expiration: 2021-12-16

Abstract

The utility model discloses an optical receiving module, which comprises a photoelectric conversion unit, a gain adjusting unit and a sampling and processing unit and is characterized by further comprising a radio frequency signal amplifying unit and a microcomputer processing unit, wherein the signal output end of the photoelectric conversion unit is respectively electrically connected to the input end of the radio frequency signal amplifying unit and the input end of the sampling and processing unit; the output end of the radio frequency signal amplifying unit is electrically connected to the gain adjusting unit; the output end of the sampling and processing unit is electrically connected to the input end of the microcomputer processing unit; and the output end of the microcomputer processing unit is electrically connected to the control end of the gain adjusting unit. The optical receiving module has the beneficial effects that: the electric level of an attenuated electric signal can be kept stable, the adjusting range of the gain adjusting unit is 0-20dB, the control range of an optical signal, which corresponds to the adjusting range of the gain adjusting unit, is also improved to a range from -8 to +2dBm, all user requirements can be met, the control precision is high, and the finally output electric signal is more stable.

Description

Optical Receivers

[technical field]

The utility model relates to optical receiving circuit, particularly a kind of Optical Receivers of automatic gain control.

[background technology]

Along with the fast development of electronic technology and optical fiber communication technology, optical-fibre communications is low because of the loss that it has, transmission frequency bandwidth, capacity is big, volume is little, electromagnetic interference in light weight, anti-, be difficult for advantages such as cross-talk, enjoys the insider to favor, and develops very fast.At present, optical fiber cable has got into the every field of wire communication, comprises fields such as post and telecommunications, broadcast communication, power communication, oil communication and military communication.Generally speaking, in order to reach farther Distance Transmission, often increase the Optical Receivers that can receive the faint light power signal at the terminal of Optical Fiber Transmission; Because optical power signals has loss in various degree in the process of transmission, so in the optical power signals of terminal node certain excursion is arranged, the jitter after amplifying; Therefore, need a control circuit to come the steady of regulating and controlling output voltage, the control range of AGC control circuit of the prior art is little; Be generally-6～0dBm; Because these two kinds of schemes all design on the mainboard, the dynamic range of index is restricted, for greater than-6～0dBm scope; Its control action is very not obvious, can not satisfy all users' the scope of application.

[utility model content]

The purpose of the utility model is to overcome above-mentioned deficiency, provides a kind of its control range big, the Optical Receivers that control precision is high.

The purpose of the utility model is to realize like this: it comprises photoelectric conversion unit (1), gain adjusting unit (3), sample processing unit (4); Its improvement is: also comprise radiofrequency signal amplifying unit (2) and computer processing unit (5); The signal output part of said photoelectric conversion unit (1) is electrically connected at the input of radiofrequency signal amplifying unit (2) and the input of sample processing unit (4) respectively; Convert light signal to the signal of telecommunication and export radiofrequency signal amplifying unit (2) to; Simultaneously, sample processing unit (4) is taked the signal of telecommunication of said photoelectric conversion unit (1) output; The output of said radiofrequency signal amplifying unit (2) is electrically connected at gain adjusting unit (3), exports the signal of telecommunication after amplifying to gain adjusting unit (3); The output of said sample processing unit (4) is electrically connected at the input of computer processing unit (5); The signal of telecommunication to taking carries out judgment processing, and exports computer processing unit (5) to through the A/D conversion, and the output of computer processing unit (5) is electrically connected at the control end of gain adjusting unit (3); The signal of telecommunication to sample processing unit (4) input carries out processing operations; Calculate the corresponding pad value of the signal of telecommunication, and export one and control signal to gain adjusting unit (3), the ride gain adjustment;

Said computer processing unit comprises first operational amplifier (U7A), second operational amplifier (U7B), the 16 resistance (R16); Wherein, The reverse input end of first operational amplifier (U7A) and output short circuit; Input is connected with the output of second operational amplifier (U7B) in the same way, positive supply termination+15V power supply, negative power end ground connection; The output of second operational amplifier (U7B) is connected to the 4th inductance (L4) in the gain adjusting unit, and the 16 resistance (R16) cross-over connection is between the output and reverse input end of second operational amplifier (U7B); The reverse input end of second operational amplifier (U7B) is through the 14 resistance (R14) ground connection; Input is connected to the input pin of sample processing unit singlechip chip (U8) through the 15 resistance (R15) in the same way; The end that the 15 resistance (R15) is connected with the input in the same way of second operational amplifier (U7B) is through the 23 electric capacity (C23) ground connection, and the 15 resistance (C15) other end is through the 13 resistance (R13) ground connection.

In the said structure; Said radiofrequency signal amplifying unit (2) comprises first order amplifying circuit (21), second level amplifying circuit (22) and transformation filter circuit (23); Described gain adjusting unit (3) is electrically connected between first order amplifying circuit (21) and the second level amplifying circuit (22), and transformation filter circuit (23) is electrically connected at the output of second level amplifying circuit (22).

In the said structure; Said sample processing unit comprises singlechip chip (U8), program input port (J2) and power supply circuits; Said power supply circuits are connected with the energization pins of singlechip chip (U8), and program input single port (J2) is connected with corresponding pin on the singlechip chip (U8).

The utility model beneficial effect is: the utility model converts light signal to the signal of telecommunication through photoelectric conversion unit, exports this signal of telecommunication to the radiofrequency signal amplifying unit and carries out the signal amplification, and the signal of telecommunication of process processing and amplifying exports gain adjusting unit to; Meanwhile, sample processing unit is taked the signal of telecommunication of photoelectric conversion unit output, and it is carried out the A/D conversion; Export computer processing unit to dc level signal; The corresponding pad value of this level signal is judged, calculated to computer processing unit to the level signal of sampling unit output, simultaneously, converts this pad value to a control signal and export gain adjusting unit to; Gain adjusting unit is carried out the decay of respective amplitude to the signal of telecommunication of radio frequency signal amplification unit circuit output; By this, make the level of the signal of telecommunication after decaying keep stable, the adjusting range of its gain adjusting unit is 0-20dB; The control range of the light signal corresponding with it also brings up to-8 to+2dBm; Satisfy all user's requests, control precision is high, and the signal of telecommunication of final output is more stable.

[description of drawings]

Fig. 1 is the theory diagram of the utility model

Fig. 2 is the schematic diagram of the utility model

[embodiment]

Below in conjunction with accompanying drawing and concrete execution mode the utility model is described further:

With reference to shown in Figure 1; The utility model has disclosed a kind of Optical Receivers; It comprises photoelectric conversion unit 1, gain adjusting unit 3, sample processing unit 4; Also comprise radiofrequency signal amplifying unit 2 and computer processing unit 5, the signal output part of said photoelectric conversion unit 1 is electrically connected at the input of radiofrequency signal amplifying unit 2 and the input of sample processing unit 4 respectively, converts light signal to the signal of telecommunication and exports radiofrequency signal amplifying unit 2 to; Simultaneously, sample processing unit 4 is taked the signal of telecommunication of said photoelectric conversion unit 1 output; The output telecommunications of said radiofrequency signal amplifying unit 2 is connected in gain adjusting unit 3, exports the signal of telecommunication after amplifying to gain adjusting unit 3; The output of said sample processing unit 4 is electrically connected at the input of computer processing unit 5; The signal of telecommunication to taking carries out judgment processing, and changes the unit 5 that exports MICROCOMPUTER PROCESSING to through A/D, and the output of computer processing unit 5 is electrically connected at the control end of gain adjusting unit 3; The signal of telecommunication to sample processing unit 4 inputs carries out processing operations; Calculate the corresponding pad value of the signal of telecommunication, and export one and control signal to gain adjusting unit 3, the ride gain adjustment.

With reference to shown in Figure 2, the pin of each unit is corresponding to be connected, and light signal gets into the photocoupler (PIN pipe) in the photoelectric conversion unit 1, converts light signal to the signal of telecommunication, carries out the 3 pin output of RF impedance coupling back from transformer T1 through transformer T1; C1, R1, R2 form the sample conversion circuit, and C1 is a filter capacitor, and C2, C3, C4, R3 form filter circuit, and L1 and C6 play impedance fine setting effect to signal.Forming of sample processing unit 4 by singlechip chip U8, program input port J2 etc.; Singlechip chip U8 is through the signal sampling of port P0.6 to photoelectric conversion unit 1; Judge through singlechip chip U8 internal processes, again through inner A/D conversion back output current signal to computer processing unit 5.Radiofrequency signal amplifying unit 2 comprises first order amplifying circuit 21, second level amplifying circuit 22 and transformation filter circuit 23; Described gain adjusting unit 3 is electrically connected between first order amplifying circuit 21 and the second level amplifying circuit 22, and transformation filter circuit 23 is electrically connected at the output of second level amplifying circuit 22.

Computer processing unit 5: comprise first operational amplifier (U7A), second operational amplifier (U7B), the 16 resistance (R16); Wherein, The reverse input end of first operational amplifier (U7A) and output short circuit; Input is connected with the output of second operational amplifier (U7B) in the same way, positive supply termination+15V power supply, negative power end ground connection; The output of second operational amplifier (U7B) is connected to the 4th inductance (L4) in the gain adjusting unit, promptly its AGC-P link corresponding with gain adjusting unit 3 in the AGC-P link be connected; The 16 resistance (R16) cross-over connection is between the output and reverse input end of second operational amplifier (U7B); The reverse input end of second operational amplifier (U7B) is through the 14 resistance (R14) ground connection; Input is connected to the input pin of sample processing unit singlechip chip (U8) through the 15 resistance (R15) in the same way; The end that the 15 resistance (R15) is connected with the input in the same way of second operational amplifier (U7B) is through the 23 electric capacity (C23) ground connection, and the 15 resistance (C15) other end is through the 13 resistance (R13) ground connection.The inner A/D conversion of singlechip chip U8 output current;, electric current produces pressure drop when arriving ground through the 13 resistance R 13 resistance; The 15 resistance R 15 is got the 13 resistance R 13 force feed that powers on and is gone into operational amplifier U7B and carry out multiple and amplify, and the multiple size is calculated by sending into operational amplifier U7B voltage swing, again through the operational amplifier computing formula calculate the 14 resistance R 14 and the 16 resistance R 16 resistance values; Back level U7A establishes water circuit, and effect is steady for protecting magnitude of voltage.

Gain adjusting unit 3: the signal of computer processing unit 3 enters in the main signal through inductance L 4, and gain is adjusted to main signal, and adjusting range is 0-20dB; Resistance R 6, resistance R 12 in order to reduce the insertion loss, can be used big resistance as the bias circuit of Q1, Q2; Controllable voltage is than higher like this; Resistance R 7, R8, R9 are suitably selected its parameter as the build-out resistor of Q1, Q2, can be in big dynamic attenuation scope correct biasing and shunting be provided for series connection and bypass Q1, Q2; Make whole networking obtain impedance matching preferably; Capacitor C 19, C20 adjust flat permanent effect to the biasing circuit slight resistance, and resistance R 10, R11 are as the flat permanent bleeder circuit of whole gain adjusting unit 3 voltages (also can be defaulted as is gain starting point circuit), and capacitor C 18, C21 are capacitances.

In sum, the utility model converts light signal to the signal of telecommunication through photoelectric conversion unit 1, exports this signal of telecommunication to radiofrequency signal amplifying unit 2 and carries out signal and amplify; The signal of telecommunication through processing and amplifying exports gain adjusting unit 3 to, and meanwhile, sample processing unit 4 is taked the signal of telecommunication of photoelectric conversion unit 1 output; And it is carried out A/D transform, exporting computer processing unit 5 to dc level signal, the corresponding pad value of this level signal is judged, calculated to the level signal of 5 pairs of sample processing units of computer processing unit, 4 outputs; Simultaneously; Convert this pad value to a control signal and export gain adjusting unit 3 to, the signal of telecommunication of 3 pairs of radio frequency signal amplification unit 2 circuit outputs of gain adjusting unit carries out the decay of respective amplitude, by this; Make the level of the signal of telecommunication after decaying keep stable; The adjusting range of its gain adjusting unit 3 is 0-20dB, and the control range of the light signal corresponding with it also brings up to-8 to+2dBm, satisfies all user's requests; Control precision is high, and the signal of telecommunication of final output is more stable.

According to the announcement and the instruction of above-mentioned specification, those skilled in the art in the invention can also carry out suitable change and modification to above-mentioned execution mode.Therefore, the embodiment that discloses and describe above the present invention is not limited to also should fall in the protection range of claim of the present invention modifications more of the present invention and change.In addition, although used some specific terms in this specification, these terms are explanation for ease just, the present invention is not constituted any restriction.

Claims

1. Optical Receivers; It comprises photoelectric conversion unit (1), gain adjusting unit (3), sample processing unit (4); It is characterized in that: also comprise radiofrequency signal amplifying unit (2) and computer processing unit (5); The signal output part of said photoelectric conversion unit (1) is electrically connected at the input of radiofrequency signal amplifying unit (2) and the input of sample processing unit (4) respectively; Convert light signal to the signal of telecommunication and export radiofrequency signal amplifying unit (2) to, simultaneously, sample processing unit (4) is taked the signal of telecommunication of said photoelectric conversion unit (1) output; The output of said radiofrequency signal amplifying unit (2) is electrically connected at gain adjusting unit (3), exports the signal of telecommunication after amplifying to gain adjusting unit (3); The output of said sample processing unit (4) is electrically connected at the input of computer processing unit (5); The signal of telecommunication to taking carries out judgment processing, and exports computer processing unit (5) to through the A/D conversion, and the output of computer processing unit (5) is electrically connected at the control end of gain adjusting unit (3); The signal of telecommunication to sample processing unit (4) input carries out processing operations; Calculate the corresponding pad value of the signal of telecommunication, and export one and control signal to gain adjusting unit (3), the ride gain adjustment;

2. Optical Receivers according to claim 1; It is characterized in that: said radiofrequency signal amplifying unit (2) comprises first order amplifying circuit (21), second level amplifying circuit (22) and transformation filter circuit (23); Described gain adjusting unit (3) is electrically connected between first order amplifying circuit (21) and the second level amplifying circuit (22), and transformation filter circuit (23) is electrically connected at the output of second level amplifying circuit (22).