There are 3 types of communication interfaces- USB Device, USB Host and LAN, of which USB Host is used to update device firmware or data storage, while USB Device and LAN are mainly used to carry out remote control between PC and device with help of provided PC software and SCPI commands.

Yes, optional OCXO improved stability to 0.1ppm and can be purchased and it's better to confirm and order it before factory shipment, because it's required to be welded on circuit.

Yes, but Pulse modulation and Pulse train same as AM, FM, and øM modulations are standard on the TFG3836. It’s no need for user to pay it additionally.

An arbitrary waveform generator (AWG) is a type of waveform generator that can produce custom waveforms, as opposed to pre-defined waveforms like sine, square, etc. It allows users to input a specific waveform shape, either through a computer interface or by uploading a waveform file, and generate the output signal accordingly. AWGs are commonly used in applications such as testing complex electronic circuits, generating signals for scientific experiments, and in the development and testing of communication systems.