User Manual DDS200 Digital Demodulation System 070-9952-00

Table of ContentsFigure 2–60: Setup for external BER measurement . . . . . . . . . . . . . . 2–80Figure 2–61: BER as a function of C/N ratio . . . . . . . . . . . . . . . . . . . . 2–83Figure 2–62: Effect of receive filter on C/N valueC/Nrec: C/N after receive filter.C/NC: C/N ahead of receive filter (in channel) . . . . . . . . . . . . . . . 2–84Figure 2–63: Assignment of parallel MPEGdata interface (X31) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–86Figure 2–64: Signals at parallel interface in 188-byte mode(STATUS: SER/PAR MPEG FRAME SIZE) . . . . . . . . . . . . . . . . . 2–87Figure 2–65: Signals at parallel interface in 204-byte mode(STATUS: SER/PAR MPEG FRAME SIZE) . . . . . . . . . . . . . . . . . 2–87Figure 2–66: Cascading of two DDS200s . . . . . . . . . . . . . . . . . . . . . . . . 2–88Figure 3–1: Tree structure of SCPI command system usingSENSe as an example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–6Figure 3–2: Instrument model with remote control viaIEC/IEEE bus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–16Figure 3–3: Status Register Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–19Figure 3–4: Overview of status registers . . . . . . . . . . . . . . . . . . . . . . . . 3–22Figure F–1: Transmission of character A in 7-bit ASCII code,even parity, 2 stop bits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F–3Figure F–2: Wiring for software handshake . . . . . . . . . . . . . . . . . . . . . F–6Figure F–3: Wiring for hardware handshake . . . . . . . . . . . . . . . . . . . . F–7DDS200 Digital Demodulation System User Manualvii