Adjacent Channel Power (ACP) is basically the ratio of the energy produced in the wanted and adjacent channels when the Transmitter is in steady state mode. Transient Adjacent Channel Power (TACP) is simply an extension of this, being the ratio of the energy produced in the wanted and adjacent channels when the Transmitter is keyed up or down. Transient ACP is measured in the frequency domain. A related parameter “Transient Behaviour” is measured in the time domain.

When the transmitter is keyed up or down (in other words, the user... Continue Reading

Before explaining Adjacent channel power, it is necessary to make mention of Electrical Noise. This subject will be covered more deeply later, but for now understand simply that noise, as it relates to communications systems, is defined as an unwanted random fluctuation in an electrical signal.

As we have seen previously, the Tx signal is produced by a locked oscillator within the Synthesizer. However, the output produced by such oscillators is not totally “clean.” That is to say that it does not just contain energy at the wanted frequency (the... Continue Reading