Keysight EXG and MXG X-Series Signal Generators User’s Guide 261
Using Custom Digital Modulation for N5172B/82B with Option 431 and 653/655/656/657
Using ARB Custom Modulation Softkeys
Custom Real-Time I/Q Baseband
The real-time mode simulates single-channel communication using user-defined modulation types
along with custom FIR filters, and symbol rates. Data can be downloaded from an external source
into PRAM memory or supplied as real time data using an external input.
The Custom Real-Time I/Q Baseband mode can also generate pre-defined data formats such as
PN9 or FIX4. A continuous data stream generated in this mode can be used for receiver bit error
analysis. This mode is limited to a single carrier.
The Custom Real-Time I/Q Baseband mode:
— has more data and modulation types available than the Arb Waveform Generator mode.
— supports custom I/Q constellation formats.
— has the capability to generate continuous PN sequences for bit error rate testing (BERT).
— needs no waveform build time when signal parameters are changed.
For more information, refer to:
— “Using the Arbitrary Waveform Generator” on page 276
— “Using the Custom Real-Time I/Q Baseband Generator” on page 302