15 research outputs found

    Cooperative Relaying with CPFSK and Distributed Space-Time Trellis Codes

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    Cooperative relaying allows single antenna users to achieve diversity and coding gains by utilizing nearby users' transmitting capabilities. We consider a relay system employing constant envelope continuous phase frequency shift keying. Distributed space-time trellis codes are implemented with a novel multiple relay protocol

    Cooperative Relaying with CPFSK and Distributed Space-Time Trellis Codes

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    Cooperative relaying allows single antenna users to achieve diversity and coding gains by utilizing nearby users' transmitting capabilities. We consider a relay system employing constant envelope continuous phase frequency shift keying. Distributed space-time trellis codes are implemented with a novel multiple relay protocol

    Space-Time Coded Systems with Continuous Phase Frequency Shift Keying

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    A space-time (ST) trellis encoded scheme with Mary continuous phase frequency shift keying with a modulationindex of 1M (M-CPFSK) is presented. A ST-M-CPFSK system model that incorporates the Rimoldi decomposition of CPFSK is developed. The Rimoldi decomposition separates the non-memory component of CPFSK from the memory component. The latter can be represented as a continuous phase encoder (CPE) and implemented with a ring convolutional encoder. The ST codes used here are linear ring convolutional codes. This allows the ST encoder and the CPE to be combined into one encoder, which can be represented by a single trellis and is easily implemented using delay elements, modulo-M adders and scalar multipliers

    Space-Time Coded Systems using Continuous Phase Modulation

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    We develop space-time trellis coded (STC) schemes using continuous-phase modulation (CPM). We employ the Rimoldi model of CPM to create a decomposed model of STC-CPM. The decomposition separates the coding from the modulation. The space-time encoding and the inherent CPM encoding is combined into a single trellis encoder on the ring of integers modulo-p. This is followed by a bank of memoryless modulators. The model allows the search for good space-time codes to take into account the inherent encoding of the modulation

    Verification of RSRM Nozzle Thermal Models With ETM-3 Aft Exit Cone In-depth Temperature Measurements

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    One of the goals of the Engineering Test Motor (ETM-3) static test was to verify analytical models through the use of instrumentation that provide real-time transient temperature response of ablating phenolic liners. Accurate measurement of in-depth temperature is critical for validating the analytical models and assessing design safety margins for nozzle insulation materials. Recent developments of in-depth thermocouple plugs have been made to more accurately measure temperature response of nozzle Liners. Thermocouple plugs were installed at two axial stations (four plugs circumferentially at each station) near the end of the ETM-3 nozzle aft exit cone to gather temperature histories during and after motor operation. The thermocouple plugs were placed at depths that bounded the reusable solid rocket motor nominal measured char depth in order to portray the carbon phenolic temperature response during the charring process. The data were used to verify the analytical models during motor operation and to better define char penetration during heat soak after motor burn out

    Randomised controlled trial and economic evaluation of podophyllotoxin solution, podophyllotoxin cream, and podophyllin in the treatment of genital warts

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    Objectives: To evaluate the efficacy and cost effectiveness of self applied podophyllotoxin 0.5% solution and podophyllotoxin 0.15% cream, compared to clinic applied 25% podophyllin in the treatment of genital warts over 4 weeks. Methods: We conducted a randomised controlled trial in 358 immunocompetent men and women with genital warts of 3 months’ duration or less. Results: In the principal analysis both podophyllotoxin solution (OR 2.93, 95% CI 1.56 to 5.50) and podophyllotoxin cream (OR 1.97, 95% CI 1.04 to 3.70) were associated with significantly increased odds of remission of all warts compared to podophyllin. We performed two further analyses. When subjects defaulting from follow up were assumed to have been cured odds of remission of all warts were also significantly increased both for podophyllotoxin solution (OR 3.04, 95% CI 1.68 to 5.49) and for podophyllotoxin cream (OR 2.46, 95% CI 1.38 to 4.40). When subjects defaulting from follow up were assumed not to have been cured odds of remission of all warts were significantly increased for podophyllotoxin solution (OR 1.92, 95% CI 1.13 to 3.27), but not for podophyllotoxin cream (OR 1.17, 95% CI 0.69 to 2.00). Local side effects were seen in 24% of subjects, and recurrence of warts within 12 weeks of study entry in 43% of all initially cleared subjects, without statistically significant differences between the treatment groups. Direct, indirect, and total costs were similar across the three treatment groups. Podophyllotoxin solution was the most cost effective treatment, followed by podophyllotoxin cream, with podophyllin treatment being the least cost effective. Conclusions: Self treatment of anogenital warts with podophyllotoxin showed greater efficacy and cost effectiveness than clinic based treatment with podophyllin
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