As 5G mobile communications are expected to
operate on networks in the 60GHz millimeter wave band, Jean Pierre Guillemet has proposed a
technique for testing multiport broadband components up to 145GHz. Although a vector network analyzer (VNA) can be used for testing at very high frequencies in the range of
several GHz to
terahertz, a more common requirement is
an instrument that operates in the 70kHz to 145GHz frequency range. Performing tests that cover this range in one scan presents
many challenges. The instrument must be capable of operating in
the low frequency range up to the millimeter wave range, which means that it must
incorporate a number of different technologies.
In addition, the VNA must have up to four ports and must be compatible with the installation on the probe station. Typical applications are measuring extremely high frequencies in imaging-type applications
in medical and defense
systems, but new applications are in mobile communications, and
the transition to 5G will require
ultra-high frequency radio transmissions up to 100 GHz.
The amplitude and phase of the reflected or transmitted wave in a VNA measurement device can be used to derive
other measurement results including power, intermodulation, noise factor, and differential mode parameters
. FIG. 2 is a simplified diagram showing the configuration of FIG. 1.
Four-port VNA. Because each test port can generate a signal source
and can measure reflections and transmissions, it must have
connectors that support broadband frequencies.
Due to the
limited bandwidth of waveguide-based connectors , they are not suitable for use, so use coaxial ports with 0.8mm connectors, which are rated up to
145GHz and capable of testing up to 150GHz. Its small size
requires careful handling, but its design prevents
damage to internal pins. & Although VNA must work properly within a certain frequency range,
some key components (such as couplers and oscillators) used in the analyzer,
so in order to cover the entire frequency band, each instrument contains
three analyzers: each The analyzers use different technologies to cover
the frequency bands from 40kHz to 2.5GHz, 2.5GHz to 30GHz, and 30GHz to 30GHz. 150GHz
