Understanding Keying Methods
When data is sent, a signal is transmitted from the transceiver. In order for the data to be transmitted, the signal must be manipulated so that the receiving station has a way of distinguishing
0s and 1s. This method of manipulating a signal so that it can represent multiple pieces of data
is known as a keying method. A keying method is what changes a signal into a carrier signal. It
provides the signal with the ability to encode data so that it can be communicated or transported.
There are three types of keying methods that will be reviewed in the following sections:
Amplitude Shift Keying (ASK), Frequency Shift Keying (FSK), and Phase Shift Keying (PSK).
These keying methods are also referred to as modulation techniques. Keying methods use two
different techniques to represent data: