Patent ID: 7187720

Claim:
A method of noise-immune information transmission, including steps of: at the transmitting side: converting a sequence of k-bit informational digital samples (k is an integer, k>1) to an analog signal using a first sampling function; supplementing the obtained analog signal with a redundant information signal; transmitting the supplemented analog signal over a communication line; at the receiving side: receiving the transmitted analog signal from the communication line; recovering from the received analog signal said sequence of informational digital samples; correcting the recovered informational digital samples using the redundant information, characterized in that the method further includes the steps of at the transmitting side: for each of n time intervals (n is an integer, n>1) consisting of m informational digital samples (m is an integer, m>1), selecting at least one benchmark point between informational samples; in each selected benchmark point, determining an analog signal value to which said m informational digital samples of the given time interval are converted using a second sampling function, in the form of (k−i)-bit sample being the least significant bits of k-bit sample (i is an integer depending on a value of operation threshold of demodulator employed at the receiving side, k>i>1); converting the samples in the n benchmark points to said redundant information signal at additional time intervals in order to supplement said analog signal; selecting a difference between power levels for transmitting the most significant i bits of each k-bit informational sample depending on a predetermined signal-to-noise ratio at the input of the receiving side, wherein, selecting the power level difference for transmitting said (k−i)-bit samples of the benchmark points, a difference between which power levels is less than a difference selected for a power levels intended for transmitting said most significant i bits in order to have a greater protection of said most significant bits from interference; at the receiving side: according to the digital k-bit samples recovered from the received signal, discovering the least significant (k−i) bits by subtraction of the most significant i bits from said recovered samples; according to the discovered least significant (k−i) bits, constructing an envelope using a second sampling function and discovering a value of this envelope in a respective benchmark point; comparing the discovered value of the envelope in the specific benchmark point with the corresponding value recovered from the received signal; in the case of coincidence of the compared values with a predetermined accuracy, deciding on a correct receiving of digital samples at the respective time interval; in the case of lack of such coincidence of said compared values, choosing a set of (k−i)-bit digital samples, which set ensures the coincidence, which is the correction.