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: 5.62 dB
Signal bits: 928
Duration: 37120 seconds, 10:18:40.00
Optimum list length: 150 (full phase search)
Optimum list length: 450 (uniform phase search only)
Percentage of channel capacity: 20.1
Additional info:
Information rate: 2.8 bits per hour
Information bits: 28.5
Outer code overhead: 9.5 bits
Inner code block size: 38 bits
Overall code rate: 1/32.56
S/N in 1Hz: -25.53 dB
Signal bandwidth: 0.025 Hz
Es/N0: -9.51 dB
Decoder memory: 1.3 Gbyte
Symbol error rate: 0.32
Shannon capacity: 13.78 bits per hour