ON7YD
PSK / BPSK tests
last updated on 18 April 2001
Block diagram of modulator
Frequency spectra
With the aim to determine the bandwidth of various (B)PSK signals I took a number of spectra :
A. CW (as reference), 12WPM and 10ms rise/fall time
B. BPSK (instant phase switching at constant amplitude), 10Bd
C. PSK (instant phase switching, AM enveloped), 10Bd
D. GPSK (gradual phase switching at constant amplitude), 10Bd and 100ms transient time (= 100%)
E. GPSK (gradual phase switching at constant amplitude), 10Bd and 50ms transient time (= 50%)
F. GPSK (gradual phase switching at constant amplitude), 10Bd and 25ms transient time (= 25%)
All spectra are taken with a Rohde & Schwarz FSEA spectrum analyzer :
Bandwidth = 3Hz
X-axis = 50Hz per division (137.5kHz center frequency)
Y-axis = 10dB per division
A. CW (12WPM, 10ms rise/fall time)
B. BPSK (10Bd)
C. PSK (10Bd)
D. GPSK (10Bd, 100ms transient time)
C. GPSK (10Bd, 50ms transient time)
D. GPSK (10Bd, 25ms transient time)
phase/time and amplitude/time diagrams
Below you find the phase versus time and amplitude versus time diagrams for each of the modes (for a 1/0 sequence) :
