This chapter includes Vector Network Analyzer (VNA) measurement capabilities and instrument architecture information. It also describes calculating and displaying S‑parameters, and describes using markers to provide additional measurement information.
The function hard keys (or main menu keys) in Vector Network Analyzer mode without Option 2 (Time Domain) are:
Freq/Dist, Scale, Sweep, Measure,Marker
The function hard keys in Vector Network Analyzer mode with Option 2 (Time Domain) are:
Freq/Time/Dist, Scale, Sweep, Measure,Marker
VNA is Vector Network Analyzer or Vector Network Analysis. The VNA Master and the LMR Master are Vector Network Analyzers that measure the magnitude and phase characteristics of 1‑port or 2‑port networks, including cables, antennas, filters, isolators, attenuators, and amplifiers. The Vector Network Analyzer compares the signal that leaves the analyzer port (the reference signal) with either the signal that is transmitted through the test device (the transmitted signal) or the signal that is reflected from the input or the output of the test device (the reflected signal).
Compared to a Scalar Network Analyzer (SNA), a VNA has the added capability for measuring phase characteristics. While phase measurements are important in themselves, the availability of this phase information unlocks many new features for complex measurements. These features include Smith Charts, Time Domain, and Group Delay. Phase information also allows greater accuracy through vector error correction of the measured signal.
A VNA can have 1-port only, in which case it measures only reflection signals. A VNA can have 2-ports, in which case it can measure both reflection and transmission. A 2-port VNA can also have two different capabilities: 1-path 2-port, or full-reversing. The 1-path 2-port design allows reflection measurements only at one of the two ports and allows transmission measurements only in one direction.
The MS20xxB VNA Master and the S412E LMR Master are two‑port, 1‑path VNA instruments that allow S11 and S21 measurements with a single connection.
The MS20xxC VNA Master is a full-reversing VNA that allows reflection measurements from both ports and allows transmission measurements in both directions (S11, S21, S22, and S12 measurements with a single connection).
Option 16 (S412E LMR Master)
With Option 0016, 6 GHz VNA Frequency Extension, all VNA functionality can be measured to 6 GHz.