Outdoor Bidirectional Optical Receiver: WR-1002-JL-ED Suppliers, Company - Hangzhou Prevail Communication Technology Co., Ltd

Performance Characteristics

● High response PIN photoelectric conversion tube.

● Optimized circuit design, SMT process production, optimized signal path, make the photoelectric signal transmission more smooth.

● Specialized RF attenuation chip, with good RF attenuation and equilibrium linear, high accuracy.

● GaAs amplifier device, power doubler output, with high gain and low distortion.

● Single Chip Microcomputer (SCM) control equipment working, LCD display the parameters, convenience and intuitive operation, and stable performance.

● Excellent AGC performance, when the input optical power range is －9～＋2dBm, the output level keep unchanged, CTB and CSO basically unchanged.

● Reserved data communication interface, can connect with the Ethernet transponder, access to network management system.

● Return emission can select burst mode to sharply decrease the noise convergence and reduce the forepart receiver number.

● ONU module optional.

Technique Parameter

Link testing conditions

The technique parameters of this manual according to the measuring method of <Specifications and methods of measurement on optical node used in CATV systems>, and tested in the following conditions.

Testing conditions:

1. Forward optical receive part: with 10km standard optical fiber, passive optical attenuator and standard optical transmitter composed the testing link. Set 59 PAL-D analog TV channel signal at range of 45/87MHz～550MHz under the specified link loss. Transmit digital modulated signal at the range of 550MHz～862/1003MHz, the digital modulated signal level (in 8 MHz bandwidth) is 10dB lower than analog signal carrier level. When the input optical power of optical receiver is -1dBm, the RF output level is 108dBμV, with 8dB output tilt, measure the C/CTB, C/CSO and C/N.

2. Backward optical transmit part: Link flatness and NPR dynamic range are the link indexes which is composed of backward optical transmitter and backward optical receiver.

Note: When the rated output level is the system full configuration and the receiving optical power is -1dBm, equipment meets the maximum output level of link index. When the system configuration reduce (that is, actual transmission channels reduce), the output level of equipment will be increased.

Friendly Notice: Suggest you setting the RF signal to 6~9dB tilt output in the practical engineering application to improve the nonlinear index (behind the node) of the cable system.

Technique Parameters

Item	Unit	Technical Parameters
Optical Parameters
Receiving Optical Power	dBm	-8 ~ +2
Optical Return Loss	dB	>45
Optical Receiving Wavelength	nm	1100 ~ 1600
Optical Connector Type		FC/APC, SC/APC or specified by the user
Fiber Type		Single Mode
Link Performance
C/N	dB	≥ 51 (-1dBm input)
C/CTB	dB	≥ 65	Output Level 106dBμV
			EQ 8dB 79ch PAL-D
C/CSO	dB	≥ 60
RF Parameters
Frequency Range	MHz	54/85/105/258 ~ 1003/1218
Flatness in Band	dB	±0.75
Rated Output Level	dBμV	≥ 106
Max Output Level	dBμV	≥ 108
Output Return Loss	dB	(54/85/105/258 ~550MHz)≥16/(550~1218MHz)≥14
Output Impedance	Ω	75
Electronic Control EQ Range	dB	0～15
Electronic Control ATT Range	dBμV	0～20
Return Optical Emission Part
Optical Parameters
Optical Transmit Wavelength	nm	1310±10, 1490±10, 1550±10, 1610±10,
		(or specified by the user)
Output Optical Power	mW	0.5, 1, 2
Optical Connector Type		FC/APC, SC/APC or specified by the user
RF Parameters
Frequency Range	MHz	5 ~ 42/65/85/204
Flatness in Band	dB	±0.75
Input Level	dBμV	72 ~ 85
Output Impedance	Ω	75
NPR Dynamic Range	dB	≥15 (NPR≥30 dB)		≥10(NPR≥30 dB)
		Use DFB laser		Use FP laser
General Performance
Supply Voltage	V	A: AC (150~265)V; B: AC (35~90)V
Operating Temperature	℃	-40~60
Storage Temperature	℃	-40~65
Relative Humidity	%	Max 95% no condensation
Consumption	VA	≤ 20
Dimension	mm	280（L）260（W）70（H）
Net Weight	kg	2.8

Note: The forward RF parameters are tested under the condition of using GaAs 25dB power doubler module in the last stage. Use other module, the parameters will be slightly different.

Burst Mode (Select this mode, see below)
Optical Output Power	dBm	-30
(Close the burst mode)	dBm	-30
Laser Turn On Threshold	dBμV	≥70
Laser Turn Off Threshold	dBμV	≤62
Laser Turn On Time (t1)	us	0.5≤ t1 ≤1
Laser Turn Off Time (t2)	us	0.5≤ t2 ≤1.5

Block Diagram

Relation Table of Input Optical Power and CNR

Function Display and Operating Instruction

Structure Diagram

	1. Optical receiving module	2. HPF (high pass filter)
	3. DS attenuator	4. CMTS DS port(without installing by default)
	5. Mainboard power supply interfafce	6. Seven-segment digital tube status display
	7. CMTS US port/EOC signal interface	8. Control mode selectable button (Enter)
	(without installing by default)	8. Control mode selectable button (Enter)
	9. Parameters adjustment button (Down)	10. Paramenters adjustment button (Up)
	11. Mainboard network mangement interface	12. Power-pass inserter
	13. Output port1	14. Optical input port
	15. RF output test port (-20dB)	16. Optical output port
	17. AC60V input port	18. Splitter or tap output
	19. Laser drive level test port (-20dB)	20. Reverse path RF input test port (-20dB)
	21. Power-pass inserter	22. Output port2
	23. LPF (low pass filter)	24. Optical transmitter module
	25. Switching power supply	26. ONU unit or transponder

Common Failure Analysis and Troubleshooting

Failure phenomenon	Failure cause	Solution
After connecting the network, the image of the optical contact point has obvious netlike curve or large particles highlights but the image background is clean.	1. The optical input power of the optical receiver is too high, make the output level of the optical receiver module too high and RF signal index deteriorate.	1. Check the optical input power and make appropriate adjustments to make it in the specified range; or adjust the attenuation of optical receiver to reduce the output level and improve index.
	2. The RF signal (input the optical transmitter) index is poor.	2. Check the front end machine room optical transmitter RF signal index and make appropriate adjustments.
After connecting the network, the image of the optical contact point has obvious noises.	1. The optical input power of the optical receiver is not high enough, results in the decrease of C/N.	1. Check the received optical power of the optical contact point and make appropriate adjustments to make it in the specified range.
	2. The optical fiber connector or adapter of the optical receiver has been polluted.	2. Improve the optical received power of the optical contact point by cleaning the optical fiber connector or adapter etc methods. Specific operation methods see “Clean and maintenance method of the optical fiber connector”.
	3. The RF input signal level of the optical transmitter is too low, make the modulation degree of the laser is not enough.	3. Check the RF input signal level of the optical transmitter and adjust to the required input range. (When the input channels number less than 15, should be higher than the nominal value.)
	4. The C/N index of system link signal is too low.	4. Use a spectrum analyzer to check the system link C/N and make appropriate adjustments. Make sure the system link signal C/N﹥51dB.
After connecting the network, the images of several optical contact points randomly appear obvious noises or bright traces.	The optical contact point has open circuit signal interference or strong interference signal intrusion.	1. Check if there is a strong interference signal source; change the optical contact point location if possible to avoid the influence of the strong interference signal source.
		2. Check the cable lines of the optical contact point, if there is shielding net or situation that the RF connector shielding effect is not good.
		3. Tightly closed the equipment enclosure to ensure the shielding effect; if possible add shielding cover to the optical contact point and reliable grounding.
After connecting the network, the images of several optical contact points appear one or two horizontal bright traces.	Power supply AC ripple interference because of the bad earth of equipment or power supply.	Check grounding situation of the equipment, make sure that every equipment in the line has been reliably grounding and the grounding resistance must be﹤4Ω.
After connecting the network, the received optical power of the optical contact point is unstable and changes continuously. The output RF signal is also unstable. But the detected optical output power of the optical transmitter is normal.	The optical fiber connector types do not match, maybe the APC type connect to PC type.	1. Check the type of optical fiber connector and adopt the APC type optical fiber connector to ensure the normal transmission of optical signal.
	The optical fiber connector or adapter may be polluted seriously or the adapter has been damaged.	2. Clean the polluted optical fiber connector or adapter. Specific operation methods see “Clean and maintenance method of the optical fiber connector”.
		3. Replace the damaged adapter.

Clean and maintenance method of the optical fiber active connector

In many times, we consider the decline of the optical power as the equipment faults, but actually it may be caused by that the optical fiber connector was polluted by dust or dirt. Inspect the fiber connector, component, or bulkhead with a fiberscope. If the connector is dirty, clean it with a cleaning technique following these steps:

1. Turn off the device power supply and carefully pull off the optical fiber connector from the adapter.

2. Wash carefully with good quality lens wiping paper and medical absorbent alcohol cotton. If use the medical absorbent alcohol cotton, still need to wait 1~2 minutes after wash, let the connector surface dry in the air.

3. Cleaned optical connector should be connected to optical power meter to measure output optical power to affirm whether it has been cleaned up.

4. When connect the cleaned optical connector back to adapter, should notice to make force appropriate to avoid china tube in the adapter crack.

5. The optical fiber connector should be cleaned in pairs. If optical power is on the low side after clean, the adapter may be polluted, clean it. (Note: Adapter should be carefully operated, so as to avoid hurting inside fiber.

6. Use compressed air or degrease alcohol cotton to wash the adapter carefully. When use compressed air, the muzzle aims at china tube of the adapter, clean
the china tube with compressed air. When use degrease alcohol cotton, insert directions need be consistent, otherwise can’t reach a good clean effect.