Psk Flashcards
What is the definition of phase modulation ?
A carrier wave is phase modulated when its phase is changed in sympathy with the amplitude of the modulating wave.
What is phase deviation ?
The amount of phase change produced by the modulating wave is called phase deviation.
What’s is phase modulation not used in ?
Practical analogue transmission systems such as speech and music
What is the carrier frequency?
The frequency occupied by the carrier in its unmodulated state
What is phase deviation ?
Maximum amount of phase change produced by the maximum modulating wave amplitude.
What is phase shift keying ? (Psk)
A special case of phase modulation in which the carrier phase is shifted between discreet phase values.
What is the minimum bandwidth equal to in psk?
The keying rate (Baud speed)
Null to null bandwidth is equal to what ?
Modulation rate x2
What significant difference does a psk have to a msk?
A drop of 13.7dB
Which type of filtering is used with regards to satellite transmissions?
Side lobe filtering.
How can we get rid of phase referencing ?
One moethod of countering phase referencing problems is to use an initial phase reference.
What can we do to stop drift ?
To resend the reference more often. This takes time and is considered wasteful
What is an amplitude ring ?
An imaginary circle drawn in a polar plot which denotes the clusters that share a common amplitude
What is a signal state ?
The total number of amplitude land phase combinations a signal can attain
What is a phase state ?
Data is represented by the phase of the signal in relation to a reference.
