Excite and analyze serial buses

Serial buses such as PCI Express and SerialATA are pushing bit rates beyond 3 GHz, making their signals look like microwaves traveling through copper traces. To test such high-speed signals, Agilent Technologies has introduced a 7-GHz pulse generator and added S-parameter analysis to its DCA-J sampling scopes.

The 81141A ($88,000, pictured) lets you produce PRBS serial data streams, clock signals, pulses, and real-world data to test receivers and data channels. It produces PRBS streams at up to 2³¹ –1 bits, and it lets you adjust duty cycles in clock signals. You can add jitter by connecting a function generator to the 81141A; the unit will modulate the signal onto its output pulses. The 81141A lets you select from return-to-zero (RZ), non-return-to-zero (NRZ), and return-to-one (R1) data patterns.

To test transmitters and data channels, Agilent has added an S-parameter option ($6000) to its DCA-J line of sampling scopes. The option, which you can download and install, lets you analyze pulsed signals in the frequency domain. Agilent Technologies, www.agilent.com.