Using the OVA’s Compression Option to Narrow Impulse Responses Broadened by Dispersion
An explanation of the OVA’s pulse compression feature and its use, including an overview of dispersion. Use of the pulse compression feature is demonstrated for two devices with highly different levels of dispersion.
The OVA’s pulse compression feature is used to compress the impulse response of a device under test by mathematically removing dispersion effects from the measured device response. This tool can be used to narrow and sharpen features in the time-delay domain that have been broadened by dispersion, and it can also allow highly dispersive devices to be characterized by the OVA. If pulse compression is not used, the impulse response durations of devices must be 6 ns or less if they are measured in transmission and half of that value or less if they are measured in reflection. This engineering note gives an overview of the OVA’s implementation of pulse compression and a brief explanation of dispersion. The use of the pulse compression option is demonstrated using two different devices: the first is a 60 m length of optical fiber that exhibits low levels of dispersion and is slightly birefringent, and the second is a highly-dispersive dispersion compensation module whose impulse response duration is too long to be accommodated by the OVA without the use of pulse compression.