FIELD: radio engineering. SUBSTANCE: device has pulse-code modulation extension unit for conversion of pulse-code modulation data to linear data, correlation unit which has set of correlators for correlation of linear data against set of given reference signals which provide detection of power range in bandwidth of two-tone signal of multiple frequency. In addition device has total power detector for detection of total power of linear data, low-band maximal power detector for detection of maximal power in lower bandwidth from values of output power of correlators which detect correlation in lower bandwidth and are located in correlation unit. In addition device has high-band maximal power detector for detection of maximal power in lower bandwidth from values of output power of correlators which detect correlation in lower bandwidth and are located in correlation unit. In addition device has decision making unit which decides whether input data are two-tone signal of multiple frequency by using total power, low-band maximal power and high-band maximal power. EFFECT: real-time detection of two-tone signal of multiple frequency in multiple- channel communication line using one digital signal processor. 6 cl, 6 dwg
