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DSP - technologies for signal processors Telephony modems family DTMF multichannel transivers Parallel radio modems Narrow bandwith Vocoders 1200 - 2400 bit/s) DSP - technologies for programmable devices Telecommunication modules in programmable devices Embedded applications	Short-wave RF modem     Digital transmission in dispersive channels (such as long range, short-wave radio chanels) requires use of special methods, adjusted to channel's characteristics. One of such method is low speed multicarrier transmission.     Short-wave RF modem for data transmission over long ranges, was implemented as software for signal procesor of TMS320C3x family. Modem uses QPSK modulation over 39 carriers, which is similar to STANAG 4197 standard. Program uses FFT algorithim for transmitter/receiver implementation.    Capabilities:    • Transmission speed 1200 bit/s or 2400 bit/s    • QPSK modulation    • Carrier number: 39    • Modulation speed: 33.333 baud    • Distance between carriers: 56.25 Hz    • Signal band: 675 – 2812.5 Hz    • Maximum allowable receivement frequency shift: 100Hz    • Maximum time of signal loss without synchronization loss < 4s