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Nonvolatile memory for data and control programs is required for advanced remote sensor systems. Simultaneous storage for data processing and data accumulation will provide versatile sensor control and optimized data link buffering. Bubble domain technology offers significant reliability and functional advantages for meeting these complicated high density memory requirements. Bubble operational capability includes multifunctional block and serial access, first-in/first-out storage, simultaneous read/write, asynchronous data rates, and expandable capacities. Several bubble device technologies have emerged in recent years. Permalloy gap devices are available commercially, while more recent device technologies such as ion implant and self-structured current accessed are in research stages. The newer device concepts are aimed at increasing storage density and data rates while minimizing power and cost. A flexible system concept is analyzed which is compatible with all of these bubble device technologies. Detailed estimates of memory system characteristics are discussed for each type of bubble device. System capacity, weight, and volume tradeoffs are dependent on the basic device data site period and on the device packaging scheme. Data rate and power dissipation are coupled to device technology, data site period, and also the device packaging scheme. Permalloy gap, ion implant, and self-structured current access systems appear to respectively offer capacities of up to 108, 109, and 1010 bits and power per unit data rate efficiencies of 140, 60, and 2 w/Mbps. Immediate term (1-2 years) systems are feasible only in permalloy gap technology. Barring unforeseen developments, near term (3-5 years) system development is expected to employ ion implant devices and longer term (7-9 years) system development could exploit self-structured current accessed devices.
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