CN107635157B

CN107635157B - Circuit for effectively shortening GPON ONU burst time

Info

Publication number: CN107635157B
Application number: CN201711025202.1A
Authority: CN
Inventors: 唐兴刚; ***; 何芯锐
Original assignee: Sichuan Tianyi Comheart Telecom Co Ltd
Current assignee: Sichuan Tianyi Comheart Telecom Co Ltd
Priority date: 2017-10-27
Filing date: 2017-10-27
Publication date: 2023-08-15
Anticipated expiration: 2037-10-27
Also published as: CN107635157A

Abstract

The invention discloses a circuit for effectively shortening the burst time of a GPON ONU, which comprises a MAC module circuit, a PMD module circuit and a GPON BOSA module circuit, wherein the MAC module circuit is connected with the PMD module circuit, the PMD module circuit is connected with the GPON BOSA module circuit, a first resistor (R1) is connected between a bias+ interface of the PMD module circuit and a LD+ interface of the GPON BOSA module circuit, and a second resistor (R2) is connected between a Bias-interface of the PMD module circuit and the LD-interface of the GPON BOSA module circuit; in order to improve the response speed of LA and increase the capability and efficiency of LA for rapidly acquiring current, the 33R resistor which is dropped by NC on BIAS-is added, and the test finds that the time from burst signal input to effective optical signal output is reduced, and the burst time of GPON ONU is shortened.

Description

Circuit for effectively shortening GPON ONU burst time

Technical Field

The invention relates to the field of photoelectricity, in particular to a circuit for effectively shortening the burst time of a GPON ONU.

Background

FTTx is in the state of development in china and is currently still in the gold-start phase compared to japan, korea and united states, china's fiber access. With the improvement of the technical level, the cost of optical communication is greatly reduced by large-scale marketing of novel optical devices and optical cables. Meanwhile, as various services requiring high-speed broadband data transmission are promoted, including IPTV (interactive network television), digital conference, interactive game, video telephone, remote medical treatment, remote learning, online shopping and Internet of things, big data and cloud computing based on smart cities are raised and promoted, the requirements of users on broadband are greatly increased, the requirements on communication quality are also greatly improved, the dial-up networking and the traditional broadband technology using copper wires for transmission can not meet the increasing bandwidth requirements any more, and governments and operators begin to increase the importance and investment on FTTx.

With the implementation of the national optical fiber broadband strategy, three operators have further increased the deployment strength of PON devices to support the development of FTTx thereof in recent years. The specific gravity of EPONs and GPONs is not a major contradiction in PON technology selection, but is determined by the characteristics of regional deployment. In the evolution of the next-generation PON technology, technologies such as 10GPON, 40G PON, and WDM-PON are the focus of industrial debate. The BOB part is in the core throat position in the whole ONU product, and mainly comprises a light driving chip, a BOSA and peripheral circuits. The BOB mainly refers to that a BOSA device is arranged on a board, so that the board-mounted integration of the BOSA is realized instead of an optical module, and the cost is reduced. Nevertheless, the bob portion costs more than 30% of the total product cost. The PON and light based BOB part will therefore be the core of the overall product, and its performance will directly determine the quality of this product.

The disadvantages of the prior art are: the existing optical driving scheme comprises a single closed loop mode and a double closed loop mode, the condition that the ONU cannot register exists in the two modes, and analysis shows that the main reason for the problem is that the burst time of the GPON ONU is too long, particularly the LA response speed is too slow, and the capacity and the efficiency of the LA for acquiring current are lower.

Disclosure of Invention

The invention aims to overcome the defects of the prior art, provide a circuit for effectively shortening the burst time of GPON ONU, improve the response speed of LA, increase the capability and efficiency of LA to acquire current rapidly, and add 33R resistance dropped by BIAS-on NC; tests are carried out, and the time from the burst signal input to the effective optical signal output can be effectively reduced, so that the burst time of the GPON ONU is shortened.

The aim of the invention is realized by the following technical scheme:

the utility model provides an effectively shorten GPON ONU burst time's circuit, includes MAC module circuit, PMD module circuit and GPON BOSA module circuit, MAC module circuit connects PMD module circuit, PMD module circuit connects GPON BOSA module circuit, connect resistance one between the Bias + interface of PMD module circuit and the GPON BOSA module circuit LD + interface, connect resistance two between the Bias-interface of PMD module circuit and GPON BOSA module circuit LD-interface.

As a further improvement of the scheme, the PMD module circuit is connected with an EEPROM.

As a further improvement of the scheme, the vcc_tx+ interface of the PMD module circuit is connected to a ground capacitor, and the Bias-interface is connected to the ground capacitor via a resistor three and to xcvr_tx_3v3.

As a further improvement of the scheme, the second resistor is a 33R resistor.

The beneficial effects of the invention are as follows: the turn-on time of the laser is about 40ns, which is significantly longer than the standard required time of 12.8 ns. In operation, when a burst signal occurs, the laser experiences a significant voltage collapse before the effective optical power is emitted, which is what lengthens the laser's on-time. The voltage collapse occurs because LA requires a larger current in a shorter time to start the laser emitting effective optical power when the laser is turned on suddenly. Since bias+ alone has limited current supply capability, voltage collapse occurs, increasing the on-time of the laser. The invention increases the capability and efficiency of LA to quickly acquire current by adding a circuit, avoids the occurrence of voltage collapse and shortens the burst time of GPON ONU.

Drawings

FIG. 1 is a schematic circuit diagram of the present invention;

fig. 2 is a waveform diagram of intensities of burst signals and effective optical signals.

Detailed Description

The technical solution of the present invention will be described in further detail with reference to the accompanying drawings, but the scope of the present invention is not limited to the following description.

As shown in figure 1 of the drawings,

the utility model provides an effectively shorten GPON ONU burst time's circuit, includes MAC module circuit, PMD module circuit and GPON BOSA module circuit, MAC module circuit connects PMD module circuit, PMD module circuit connects GPON BOSA module circuit, connect resistance R1 between the Bias + interface of PMD module circuit and the GPON BOSA module circuit LD + interface, connect resistance two R2 between the Bias-interface of PMD module circuit and the GPON BOSA module circuit LD-interface.

As a further development of the solution, the vcc_tx+ interface of the PMD module circuit is connected to a ground capacitor C, and the Bias interface is connected to the ground capacitor C via a resistor tri R3 and to xcvr_tx_3v3.

As a further improvement of the scheme, the resistor two R2 is a 33R resistor.

As shown in fig. 2:

the graph is a waveform diagram of the intensity of a burst signal and an effective optical signal, the burst signal is generated at the time X1, the optical signal is stable at the time X2, and the voltage collapse appears before the time X2, so that the voltage collapse increases the starting time of the laser. Simultaneously for this patent provides the thinking: the circuit is added to increase the capability and efficiency of the LA to quickly acquire current, so that the occurrence of voltage collapse is avoided, and the burst time of the GPON ONU is shortened.

The foregoing is merely a preferred embodiment of the invention, and it is to be understood that the invention is not limited to the form disclosed herein but is not to be construed as excluding other embodiments, but is capable of numerous other combinations, modifications and environments and is capable of modifications within the scope of the inventive concept, either as taught or as a matter of routine skill or knowledge in the relevant art. And that modifications and variations which do not depart from the spirit and scope of the invention are intended to be within the scope of the appended claims.

Claims

1. The utility model provides an effectively shorten GPON ONU burst time's circuit, includes MAC module circuit, PMD module circuit and GPON BOSA module circuit, MAC module circuit connects PMD module circuit, PMD module circuit connects GPON BOSA module circuit, connecting resistance one (R1) between the bias+ interface of PMD module circuit and the GPON BOSA module circuit LD+ interface, its characterized in that: a resistor II (R2) is connected between the Bias-interface of the PMD module circuit and the LD-interface of the GPON BOSA module circuit;

the PMD module circuit is connected with an EEPROM, a VCC_TX+ interface of the PMD module circuit is connected with a grounding capacitor (C), and a Bias-interface is connected with the grounding capacitor (C) through a resistor III (R3) and is connected with an XCVR_TX_3V3;

the resistor two (R2) is 33R resistor.