High-Stability Time Base Reduces Frequency Drift
Now every ESG vector signal generator is equipped with Option 1E5, free of charge. This option provides an oven-controlled crystal oscillator (OCXO) as the internal time base reference. This high-stability time base has a lower aging rate compared to the standard temperature controlled crystal oscillator (TCXO) time base. The low aging rate reduces frequency drift, which results in improved frequency accuracy over time. Wondering what affects frequency accuracy and how it is determined? More information
The close-in phase noise performance of the high stability time base is also improved over the standard TCXO. When generating the test stimulus, there are two levels of phase noise performance selectable from the user interface: 1) optimize close-in phase noise performance and 2) optimize mid-range phase noise performance. View plot
To further improve the phase noise performance of the E4438C ESG, refer to Option UNJ enhanced phase noise performance, which includes the same performance as Option 1E5.
Typical Applications
The high-stability time base is recommended for precise frequency accuracy and improved close-in phase noise performance. Complex transmission schemes, such as OFDM (orthogonal frequency division multiplexing) used for 802.11a and 802.11g WLAN, demand precise frequency accuracy from the test stimulus. The enhanced phase noise performance is beneficial for a variety of applications, including high order modulation schemes like 64 and 128 QAM, LO substitution, and jitter measurements.
This option can be added as a product upgrade.