expressed as a percentage. With the transmitter driven by a 25 MBd (12.5 MHz square-wave) input signal, the average optical power is measured. The data “1” peak power is then calculated by adding 3dB to the measured average optical power. The data “0” output optical power is found by measuring the optical power when the transmitter is driven by a logic “0” input. The extinction ratio is the ratio of the optical power at the “0” level compared to the optical power at the “1” level expressed as a percentage or in decibels.
11.The transmitter will provide this low level of Output Optical Power when driven by a logic “0” input. This can be useful in link troubleshooting.
12.The relationship between Full Width Half Maximum and RMS values for Spectral Width is derived from the assumption of a Gaussian shaped spectrum which results in a 2.35 X RMS = FWHM relationship.
13.The optical rise and fall times are measured from 10% to 90% when the transmitter is driven by a 25 MBd (12.5 MHz square-wave) input signal. The ANSI T1E1.2 committee has designated the possibility of defining an eye pattern mask for the transmitter optical output as an itemforfurtherstudy.Agilent will incorporate this requirement into the specifications for these products if it is defined. The HFBR-5204 and HFBR-5205 products typically comply with the template require- ments of CCITT (now ITU-T) G.957 Section 3.2.5, Figure 2 for the STM- 1 rate, excluding the optical receiver filter normally associated with single mode fiber measurements which is the likely source for the ANSI T1E1.2 committee to follow in this matter.
14.Systematic Jitter contributed by the transmitter is defined as the com- bination of Duty Cycle Distortion and Data Dependent Jitter. Systematic Jitter is measured at 50% threshold using a 155.52 MBd (77.5 MHz square-wave), 27 - 1 psuedorandom data pattern input signal.
15.Random Jitter contributed by the transmitter is specified with a 155.52 MBd (77.5 MHz square- wave) input signal.
16.This specification is intended to indicate the performance of the receiver section of the transceiver when Input Optical Power signal characteristics are present per the following definitions. The Input Optical Power dynamic range from the minimum level (with a window time-width) to the maximum level is the range over which the receiver is guaranteed to provide output data with a Bit Error Ratio (BER) better than or equal to 1 x 10-10.
• At the Beginning of Life (BOL)
• Over the specified operating temperature and voltage ranges
• Input is a 155.52 MBd, 223 - 1 PRBS data pattern with 72 “1”s and 72 “0”s inserted per the CCITT (now ITU-T) recommenda- tion G.958 Appendix I.
• Receiver data window time-width is 1.23 ns or greater for the clock recovery circuit to operate in. The actual test data window time- width is set to simulate the effect of worst case optical input jitter based on the transmitter jitter values from the specification tables. The test window time- widths are as follows: HFBR-5203 is 4.4ns, HFBR-5205 and HFBR- 5204 are 3.32 ns.
•Transmitter operating with a
155.52MBd, 77.5 MHz square- wave, input signal to simulate any cross-talk present between the transmitter and receiver sections of the transceiver.
17.All conditions of Note 16 apply except that the measurement is made at the center of the symbol with no window time-width.
18.Systematic Jitter contributed by the receiver is defined as the combina- tion of Duty Cycle Distortion and Data Dependent Jitter. Systematic Jitter is measured at 50% threshold using a 155.52 MBd (77.5 MHz square-wave), 27 - 1 psuedorandom data pattern input signal.
19.Random Jitter contributed by the receiver is specified with a 155.52 MBd (77.5 MHz square-wave) input signal.
20.This value is measured during the transition from low to high levels of input optical power.
21.This value is measured during the transition from high to low levels of input optical power.
22.The Signal Detect output shall be asserted within 100 μs after a step increase of the Input Optical Power.
23.Signal detect output shall be de- asserted within 350 μs after a step decrease in the Input Optical Power.
24.The HFBR-5205 transceiver complies with the requirements for the tradeoffs between center wave- length, spectral width, and rise/fall times shown in Figure 9. This figure is derived from the FDDI PMD standard (ISO/IEC 9314-3 : 1990 and ANSI X3.166 - 1990) per the description in ANSI T1E1.2 Revision 3. The interpretation of this figure is that values of Center Wavelength and Spectral Width must lie along the appropriate Optical Rise/Fall Time curve.
