TABLE OF CONTENTS Network measurements can be divided into two types-transmission through the network and reflection at the network's input or output port. Full two-port network analysis normally requires the use of a multichannel network analyzer and an s parameter test set. Simpler measurements, such as transmission-only measurements, can be performed with less sophisticated equipment.
The transmission through a two-port network is measured by applying a signal to one port and measure the response at the other port (Figure 14-1). The forward transmission characteristics of a network are measured by connecting the signal source to the input port and measuring the response at the output port. The reverse transmission characteristics of the network can be measured by driving the network at the output port and measuring the response at the input.
The reflection at the input port of a network is measured by applying a signal to the port and measuring the traveling wave reflected by the input. The reflection at the output port can be measured in a similar manner, while driving the output port.
An oscilloscope and a sweep generator can be used to implement a simple scalar network analyzer (Figure 14-2). This measurement setup is useful for making transmission measurements when only the magnitude (and not the phase) of the transfer function is required. The oscilloscope is operated in X-Y (channel versus channel) mode with the X (horizontal) input...
