MINIATURIZED RADIO RELAY FOR UHF/VHF COMMUNICATIONS

RADIO RELAYS INSTALLED ON ELEVATED PLATFORMS SUCH AS KITES AND BALLOONS CAN EXTEND LINE-OF-SIGHT VHF AND UHF COMMUNICATIOS RANGE BEYOND THE HORIZON. THESE RELAYS MUST BE LIGHTWEIGHT, OPERATE FOR SEVERAL HOURS ON SELF-CONTAINED BATTERIES, AND, BECAUSE THEY ARE EXPENDABLE ITEMS, BE LOW COST. A REPEATER WILL BE DEVELOPED USING CURRENT LOW-COST TECHNOLOGY THAT WILL SIMULTANEOUSLY REPEAT THREE COMMUNICATION CHANNELS, TWO 25 KHZ AM VOICE AND ONE 25 KHZ FM DATA CHANNEL. THE REPEATER USES AN IF REPEATER ARCHITECTURE, WITH THREE INDEPENDENT CHANNELS, EACH FREQUENCY SELECTED BY A PROGRAMMABLE SYNTHESIZER. THE THREE CHANNELS ARE TRANSLATED BY A CONSTANT FREQUENCY SHIFT, AND SUMMED TOGETHER. THE COMPOSITE SIGNAL IS AMPLIFIED BY A LINEAR AMPLIFIER TO 5 WATTS PER CHANNEL AND RETRANSMITTED. A DIPLEXER SEPARATES THE RECEIVE AND TRANSMIT BANDS TO ALLOW A COMMON ANTENNA. THE REPEATER WILL OPERATE FOR 12 HOURS WITH 50% DUTY CYCLE. THE REPEATER USES RECENTLY DEVELOPED LOW-POWER RF AND IF INTEGRATED CIRCUITS, HIGH ENERGY BATTERIES, AND LOW COST MINIATURE PACKAGING TECHNIQUES TO PROVIDE THE ENTIRE ELECTRONICS WITH BATTERIES IN A SIX POUND PACKAGE SUITABLE FOR BALLOONS. THE DEVELOPMENT WILL PROVIDE A SYSTEM ARCHITECTURE AND BUILDING BLOCK MODULE DESIGNS SUITABLE FOR REPEATERS OPERATING IN THE VHF AND UHF FREQUENCY BANDS. THE IF REPEATERS ARE NOT LIMITED TO SPECIFIC MODULATION FORMATS AND CAN BE ADAPTED TO MOST NARROWBAND SIGNALS.