The famous "Wow" signal detected in 1977 remains arguably the most compelling SETI ever found. original Big Ear data requires that turned on/off over span of ~3 minutes (time difference between dual antennae), yet persisted for 72 seconds (duration a single beam sweep). Combined with substantial and negative follow-up efforts, these observations limit allowed range repeat schedules, to extent o...

Radio beacons on satellites can be used in conjunction with ground receivers to study the ionosphere. The flexibility of new wideband tuners and digital receiver platforms requires a modular, adaptable software chain to optimally process and interpret beacon overflight data. A python-based system was developed to track the beacon, filter noise, and convert the signal to baseband. The slow but i...

The mechanism for finding the position of sensor node is crucial for many sensor network applications. Most sensor networks which can tolerate coarse accuracy look range free localization mechanism as its solution. We have proposed a novel algorithm where beacon nodes are randomly distributed and sensor nodes estimates the beacon nodes at different levels according to signal strength. We determ...

Over the past 3 years, JPL has been heavily engaged in designing and developing a reduced-complexity optical communication terminal for high-data-volume applications. The terminal is called the Optical Communication Demonstrator (OCD) and has the ability to point microradian-level beams with a very small number of detectors and steering elements. Using only a single steering mirror and a charge...

We investigated three probe design strategies used in quantitative polymerase chain reaction (PCR) for sensitivity in detection of the PCR amplicon. A plasmid with a 120-bp insert served as the DNA template. The probes were TaqMan, conventional molecular beacon (MB), and shared-stem molecular beacon (ATssMB and GCssMB). A shared-stem beacon probe combines the properties of a TaqMan probe and a ...

The design of a low-cost beacon receiver based on software defined radio is presented. The motivation for such a receiver is to investigate atmospheric impairments at the Ka frequency band. The receiver has been tested by the Hotbird 13A, ASTRA 3B and Alphasat satellite beacon signals. A GNU Radio software development toolkit and a USRP device were used for the development of a beacon receiver ...

Molecular beacon probes can be employed in a NASBA amplicon detection system to generate a specific fluorescent signal concomitantly with amplification. A molecular beacon, designed to hybridize within the target sequence, was introduced into NASBA reactions that amplify the genomic RNA of potato leafroll virus (PLRV). During amplification, the probe anneals to the antisense RNA amplicon genera...

In this paper we present a user-centric position sensing system that is based on asynchronous, independent ultrasonic beacons. These stationary transmitter units are small, cheap to manufacture, and have power requirements low enough to run each from a small solar cell and a nearby light source. Each beacon is programmed to emit a short, 40 kHz ultrasonic signal with a unique transmission perio...

This document is disseminated under the sponsorship of the Department of Transportation in the interest of information exchange. The United States Government assumes no liability for its contents or use thereof. 6. Abstract GPS-Squitter is a system concept that merges the capabilities of Automatic Dependent Surveillance (ADS) and the Mode S beacon radar. The result is an integrated concept for ...

The time required to search a buried person using an avalanche beacon contributes significantly to the overall rescue time. This paper investigates the technical requirements and psychological demands with respect to minimal search time. The earlier ones define a beacon's technical specification, the latter ones the design of the user interface. The first search phase is mainly characterized by...