1. 1394b Design for Gigabit Optoelectronic Data Communication
Group G9:
Tiffany Lovett, gte291r
Tornya Moore, gte668r
Presented By:
Mareisha Winters, gte824t
ECE 4006 C
Spring 2002

2. Objective Design Considerations for OE components Link Budget Analysis
Testing Procedures

3. Design Considerations for the VCSEL
Two candidates:
Honeywell HFE
Honeywell HFE
Threshold current-minimum amount of current needed for the VCSEL to emit light
Slope Efficiency-tells how many amps it takes to produce a given power output
Rise/Fall Times

4. Comparison of Two VCSEL Candidates
HFE
HFE

5. Design Considerations for the Photodetector
Two candidates:
Lasermate RSC-M85A306
Hamamatsu S5973
Responsivity-measures how much light input is required to produce a given current
Capacitance of the photodiode must not exceed the maximum input capacitance of the MAXIM board.
Rise/Fall Time

6. Comparison of Two Photodiode Candidates
Lasermate RSC-M85A306
Hamamatsu S5973

7. Link Budget Analysis Will the system work for the proposed link?
For this project the purpose of the link budget is to determine whether the transmitter and receiver system provide sufficient current to drive the post amp.
Link Budget = Power Incident on Photodetector x Responsivity of the Photodetector
Power Incident on Photodetector = [Modulation Current of Transmitter x Slope Efficiency of VCSEL] – Losses Due to Connectors and Fiber

8. Link Budget Analysis (Cont’d)

9. Testing
The PIN photodiode and VCSEL will be connected to their own separate boards and connected via optical fiber. These boards will then be connected to the MAXIM Evaluation Kits.
The two pieces of equipment that will be used to verify the functionality of the components are the Tektronix GTS 1250 Bit Error Rate Test Set (BERTS) and Tektronix 7000 Series Oscilloscope.

10. Testing (cont’d)
The BERTS measures the bit error rate (BER) for a given transmission.
The BER is the percentage of bits that have errors relative to the number of bits received.
BER ~ 10-12
The oscilloscope displays the data stream as information is transmitted. The data transmission creates an eye pattern.
The preferred sampling time is when the eye is opened the widest.