Learning programming in early introductory classes is challenging for first year university students, and introducing parallel programming (PDC) in early classes along with traditional sequential programming is even more challenging. Unplugged activities may help alleviate some of the difficulties for students. Unplugged activities have been shown to increase student interest, and to enhance student understanding of CS programming concepts. We have used unplugged activities to teach PDC concepts before introducing parallel programming. Our experiences show that using unplugged activities to introduce the PDC concepts reduce the barrier to learn parallel programming.

This paper describes the experience of redesigning a traditional CS1 programming course, utilizing traditional coding practices as well as microcontroller units (MCU) based coding, to provide multiple programming environments. The objective of this redesign is to improve the programming skills for engineering students by 1) providing them with program development experience in multiple contexts and 2) relating the initial programming experience to the typical notion of engineering through significant hardware experience. Typical CS1 courses are designed with an instructor led lecture focusing on the introduction of specific computer skills and languages while programming assignments and laboratories help strengthen these skills in the students. For this remodeling, in addition to the typical programming exercises, supplementary MCU based lab exercises were used to provide an additional, different programming target for increased learning and highlighting the complementary relationship between hardware and software. The outcomes of this effort demonstrate that the addition of a MCU to an introductory programming course can work as an effective motivator, providing the students with a secondary context to reinforce programming skills developed during the course, and that providing multiple contexts (traditional desktop programming and hardware-based programming) together can aid in learning and the transfer of knowledge.

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This paper describes a meteor-burst communication model based on physical models and astronomical observations of meteor orbits and flux. It compares model results to experimental results and uses them to illuminate this complex propagation medium and to show how "hot spots" of meteor activity vary in position and relative importance with the fundamental meteor-burst link parameters. It also presents antenna and other meteor-burst link design considerations with emphasis on military systems.

This paper describes the design and performance of a spread-spectrum medium frequency (MF) radio network. The network utilizes a simulcast time slotted transmission scheme in which radios that receive a data message in one time slot repeat the message in the next slot. Spread-spectrum radio designs that operate efficiently with simulcast under a variety of channel conditions are investigated. The performance of the radio network is characterized in terms of radio connectivity and message reaction time.

Three different ground terminal transmit power control concepts for a Satcom system are examined. The effectiveness of constant satellite power (CSP) sharing among the carriers and adaptive satellite power (ASP) sharing is compared with constant ground terminal transmit power (CTP). It is shown that ASP offers substantial advantages over CSP in combating environmental degradations and that both can increase link availability with respect to the constant power (CTP) case. The effectiveness of the ASP control technique is shown to depend on the interconnectivity of the network if multidestinational carriers are used. The measurements required for system control, as well as their accuracies, are described.