FS-1016 (also called FED-STD-1016) is a deprecated
secure telephony speech encoding
Speech coding is an application of data compression of digital audio signals containing speech. Speech coding uses speech-specific parameter estimation using audio signal processing techniques to model the speech signal, combined with generic d ...
standard for
Code-excited linear prediction (CELP) developed by the
United States Department of Defense
The United States Department of Defense (DoD, USDOD or DOD) is an executive branch department of the federal government charged with coordinating and supervising all agencies and functions of the government directly related to national secur ...
and finalized February 14, 1991.
Unlike the vocoder used in
FS-1015 FIPS 137, originally issued as FED-STD-1015, is a secure telephony speech encoding standard for Linear Predictive Coding vocoder developed by the United States Department of Defense and finished on November 28, 1984.
It was based on the earlier STA ...
,
CELP provides more natural speech. However, due to quite low bit rate and early development (1991), the speech quality is very noisy and below that of commercial cellular speech codec such as
AMR. FS-1016 is no longer used since its follow-up
MELP provides better performance in all applications.
Technical details
The bit rate of the codec is 4.8 kbit/s. The complexity of the codec is 19
MIPS. The
RAM
Ram, ram, or RAM may refer to:
Animals
* A male sheep
* Ram cichlid, a freshwater tropical fish
People
* Ram (given name)
* Ram (surname)
* Ram (director) (Ramsubramaniam), an Indian Tamil film director
* RAM (musician) (born 1974), Dutch
...
requirement is 1.5 kilobytes. Frame size of the codec is 30 ms.
Look-ahead of 7.5 ms is also required.
The variation of
CELP used in the FS-1016 is so-called ternary codebook, meaning that all excitation amplitudes are either +1, −1 or 0. The sub frame gain is calculated and sent to the receiver.
References
External links
"CELP-3.2a and LPC-10"Speech at Carnegie Mellon University
Speech codecs
{{telecom-stub