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Antenna performance parameters measurement is important for verifying computation, simulation, and analysis results. For measuring circuit parameters such as scattering parameters (S_ii/S_ij), where S_ii and S_ij refer to self‐port reflection coefficient and coupling port transmission coefficient, vector network analyzers are preferred after proper calibration [6]. For example, Figure 1.15 shows photographs of vector network analyzers from Anritsu and Keysight, both of which are available at the Antenna and Microwave Laboratory (AML), San Diego State University.

For measuring radiation patterns, we can use far‐field, near‐field, and compact antenna test range (CATR) chambers. Figure 1.16 shows photographs of the far‐field and CATR anechoic chambers at the AML, San Diego State University. The first anechoic chamber is shown in Figure 1.16a, which is capable of far‐field radiation measurements. It can cover a frequency range from 800 to 40 GHz. The chamber comes with ORBIT/FR 959 acquisition measurement software and provides measurement results for 2D/3D radiation pattern, realized gain, and polarization with sense of rotation.

The Mini‐Compact Antenna Test Range (M‐CATR) from Microwave Vision Group (MVG) for millimeter‐wave antenna measurement covers frequencies between 26.5 and 110 GHz, as shown in Figure 1.16b. Keysight N5225A Power Network Analyzer (PNA) serves its signal power generator that ranges from 10 to 50 GHz. The frequency is extended up to 110 GHz using proper external frequency extenders: V‐band (50–75 GHz) and W‐band (75–110 GHz). This chamber is capable of measuring realized gain, 2D and 3D radiation patterns, and polarization of the antenna with the sense of rotation using the ORBIT/FR 959 acquisition measurement software.

Interested readers should review text books on the theory behind antenna radiation pattern measurements such as [1].

Figure 1.15 Vector network analyzer (VNA) can be used for measurement of the scattering parameter: (a) Anritsu's VNA and (b) Keysight's VNA.

Figure 1.16 Antenna testing in anechoic chamber at the Antenna and Microwave Laboratory (AML), San Diego State University: (a) far‐field anechoic chamber covering 800–40 GHz and (b) Mini‐Compact Antenna Test Range (M‐CATR) system covering 26.5–110 GHz.