Patent ID: 11927661
Assignee: KEYSIGHT TECHNOLOGIES, INC.
Field: Telecommunications (Electrical engineering)
Classification: CPC G  H | IPC G  H

Claim 0:
1. A method of calibrating a test system, comprising a first test instrument connected to a second test instrument, the first test instrument including a vector network analyzer (VNA), a first radio frequency (RF) source, a first receiver and a second receiver, and the second test instrument including a second RF source, the method comprising:
connecting a first test port of the first test instrument to a second test port of the second test instrument;
generating a first RF signal using the first RF source of the first test instrument, while the second RF source of the second test instrument is turned off;
receiving a first incident signal of the first RF signal at the first receiver of the first test instrument, and receiving a first reflected signal at the second receiver of the first test instrument;
measuring a first phase of the first RF signal at the first test port using the received first incident signal and the received first reflected signal;
generating a second RF signal using a second RF source of the second test instrument, while the first RF source of the first test instrument is turned off;
receiving a second incident signal of the second RF signal at the second receiver of the first test instrument, and receiving a second reflected signal at the first receiver of the first test instrument;
measuring a second phase of the second RF signal at the first test port using the received second incident signal and the received second reflected signal;
determining a phase difference between the first phase and the second phase; and
adjusting at least one of the first RF source and the second RF source by a phase adjustment amount to remove the determined phase difference and to phase align the first and second RF sources.