Three Receivers Calibration: mention NanoVNA as motivation.
scikit-rf already contains a NanoVNA calibration example.
It's expected to be a significant user of the three-receiver
calibration technique. Thus, mention NanoVNA at the beginning
of the guide as motivation.
"source": [
"It has long been known that full error correction is possible given a VNA with only three receivers and no internal coaxial switch. However, since no modern VNA employs such an architecture, the software required to make fully corrected measurements is not available on today's modern VNA's. \n",
"\n",
- "Recently, the application of Frequency Extender units containing only three receivers has become more common. Thus, there is a need for full error correction capability on systems with three receivers and no internal coaxial switch. This document describes how to use [scikit-rf](http://www.scikit-rf.org) to fully correct two-port measurements made on such a system."
+ "Recently, the application of Frequency Extender units containing only three receivers has become more common. Furthermore, low-cost VNAs are becoming useful tools for learning RF electronics. The representative example is NanoVNA, which uses a three-receiver design. Thus, there is a need for full error correction capability on systems with three receivers and no internal coaxial switch. This document describes how to use [scikit-rf](http://www.scikit-rf.org) to fully correct two-port measurements made on such a system."
]
},
{
