SHF has further improved the SHF 11104 A error analyzer (EA)

PAM-4 is getting more and more popular as it transmits twice the information at the same Baud-rate as traditional NRZ. New data- and telecommunication standards such as 400 GbE are already utilizing this approach.

On the transmit site SHF’s digital-to-analog converters (DACs) are a well-established source of high speed PAM in all its variations (even with pre-emphasis or unequal amplitude spacing).  There is simply no other more cost-effective way to produce robust PAM signals with rise times as fast and signal quality as good as from SHF DACs. Further information on our DAC modules can be found here.

On the receive site, however, a real time bit error ratio (BER) analysis of PAM signals is not as straight forward as for binary signals.  To assist our customer in this measurement task SHF has further improved  the SHF 11104 A error analyzer (EA) to perform PAM-4 BER analysis up to 33 GBaud. Here, the user pattern capability enables the EA to measure the individual error rates in each of the three eye openings.

SHF pam-4 solution

BPG + DAC generate PAM Signal to be analyzed by the EA

Further, a new software feature has been introduced to provide an automated routine to determine the optimum sampling points within each of the three concurrent eye openings, to visualize the measurement results and calculate the overall PAM-4 BER.

SHF pam-4 analysis

BER Measurement and Eye Contour Scan of a PAM-4 Signal

The full data sheet of the SHF 11104 A EA can be downloaded here.