Signal Calculator

Carrier Measurement

Measure the S/N ratio of the steady carrier using the longest possible coherent measurement time (narrowest bandwidth) to obtain an average S/N. Ideally, use a similar time of day and duration to the intended messages.

S/N ratio of carrier:  dB   In bandwidth:  Hz, or measurement period:  seconds

Code Selection

Choose a code, symbol period, message length and decoder list size. Choose the constraint length K according to the capacity of your decoding computer. If you are confident of the clock accuracy of the PCs at both ends, choose a rate 1/16 code, otherwise rate 1/8 is a safer bet.

Select code:
  Rate 1/4 K = 19
  Rate 1/8 K = 19
  Rate 1/16 K = 19
  Rate 1/8 K = 21
  Rate 1/16 K = 21
  Rate 1/16 K = 23
  Rate 1/8 K = 25
  Rate 1/16 K = 25

Symbol period:  seconds     CRC bits:     Number of characters: 


Calculation Results

Eb/N0: -0.33 dB
Signal bits: 2432
Duration: 72960 seconds, 20:16:00.00
Optimum list length: Very large (full phase search)
Optimum list length: Very large (uniform phase search only)
Percentage of channel capacity: 78.4
Additional info:
Information rate: 12.7 bits per hour
Information bits: 256.5
Outer code overhead: 29.5 bits
Inner code block size: 286 bits
Overall code rate: 1/9.48
S/N in 1Hz: -24.87 dB
Signal bandwidth: 0.033 Hz
Es/N0: -10.1 dB
Decoder memory: 1.6 Gbyte
Symbol error rate: 0.33
Shannon capacity: 16.14 bits per hour