... Frequency Shift Keying (GFSK) modulation, High anti-interference and Low BER (Bit error Rate); * Half duplex: ... AMR), * Wireless smart terminal: POS, PDA,* Wireless alarm and security systems , PTZ,* Wireless electronic display screen, LED display,* ... monitors, telemetry system; * Check attendance system, Queue-management system and positioning in coal mine; * Industrial automatic data collection, ...