3,542 research outputs found
Automatic-repeat-request error control schemes
Error detection incorporated with automatic-repeat-request (ARQ) is widely used for error control in data communication systems. This method of error control is simple and provides high system reliability. If a properly chosen code is used for error detection, virtually error-free data transmission can be attained. Various types of ARQ and hybrid ARQ schemes, and error detection using linear block codes are surveyed
Processing and Transmission of Information
Contains reports on four research projects.Lincoln Laboratory, Purchase Order DDL-B222U.S. Air Force under Air Force Contract AF19(604)-520
Error Exponents for Variable-length Block Codes with Feedback and Cost Constraints
Variable-length block-coding schemes are investigated for discrete memoryless
channels with ideal feedback under cost constraints. Upper and lower bounds are
found for the minimum achievable probability of decoding error as
a function of constraints R, \AV, and on the transmission rate,
average cost, and average block length respectively. For given and \AV,
the lower and upper bounds to the exponent are
asymptotically equal as . The resulting reliability
function, , as a
function of and \AV, is concave in the pair (R, \AV) and generalizes
the linear reliability function of Burnashev to include cost constraints. The
results are generalized to a class of discrete-time memoryless channels with
arbitrary alphabets, including additive Gaussian noise channels with amplitude
and power constraints
- β¦