Created by: Peter Martinez G3PLX
Baud rate : 31.25
Speed : 37 wpm in capital letters and 51 wpm in small letters (average)
Modulation : DBPSK
Receive mode: indifferent (LSB or USB) for BPSK31 only, for QPSK31 USB is mandatory
Character set : ASCII characters + ANSI extended characters + an error reset character («
Varicode » characters)
Shape of pulse : raised cosine
Bandwidth : about 80 Hz,
Demodulation : coherent,
Synchronization : automatic using the signal
Correction code : no
Convolution code : no for BPSK31, yes for QPSK31 (Rate=1/2, Constraint length=5, use of Viterbi decoder with soft decison)
Interleaving : no
Automatic Frequency Correction : about +/- 10 Hz depending on signal-to-noise ratio,
Drift tolerance : 60 Hz/min in BPSK31 and 20 Hz/min in QPSK31 (depending on level)
Pmean/Ppeak : 0.79 for BPSK31 and 0.35 for QPSK31
Lowest S/N : -11.5 dB
Note : the BPSK31 mode is very much used, QPSK31 is not used that much
+Comfortable speeds for ragchewing
-Does not handle multipathing, selective fading , doppler shifting as well as wider modes do especially on the long haul dx
+Real good signal to noise ratio meaning not as much power is required.
+Very popular around the world
+Due to the small bandwidth you can fit many operators in a traditional sized SSB passband.
-The audio can be easily overdriven and cause alot of QRM
+Good for contests with moderatly high scores.
+Alot of clubs promote the mode for awards,contest etc.
-QPSK is not used vey often
-QPSK is SSB dependant meaning both OM need to be on same SSB
+QPSK has slightly less errors compared to BPSK
BPSK31 Varicode list Here