Keyword: Transmissions

Briefs: Photonics/Optics
Inter-Symbol Guard Time for Synchronizing Optical PPM

An inter-symbol guard time has been proposed as a means of synchronizing the symbol and slot clocks of an optical pulse-position modulation (PPM) receiver with the symbol and slot periods of an incoming optical PPM signal. (Such synchronization is necessary for correct identification of...

Articles: Robotics, Automation & Control

Slip clutches are commonly used to protect against overloads, but they can solve many other problems as well. Their applications include increasing machine speeds, applying constant tension to webs...

Briefs: Software
DSN Data Visualization Suite

The DSN Data Visualization Suite is a set of computer programs and reusable Application Programming Interfaces (APIs) that assist in the visualization and analysis of Deep Space Network (DSN) spacecraft-tracking data, which can include predicted and actual values of downlink frequencies, uplink frequencies, and...

Briefs: Physical Sciences

A method for real-time detection of dust devils at a given location is based on identifying the abrupt, temporary decreases in atmospheric pressure that are characteristic of dust...

Briefs: Information Technology
TCP/IP Interface for the Satellite Orbit Analysis Program (SOAP)

The Transmission Control Protocol/Internet protocol (TCP/IP) interface for the Satellite Orbit Analysis Program (SOAP) provides the means for the software to establish real-time interfaces with other software. Such interfaces can operate between two programs, either on the same...

Articles: Motion Control

Single-turn encoders have long been used in industrial automation to gauge angular displacement in a broad range of applications, ranging from steering control on a mobile equipment...

Briefs: Electronics & Computers

A breadboard version of a transmitter for radio communication at a carrier frequency of 32 GHz (which is in the Ka band) utilizes a vector modulator operating at a carrier frequency...

Briefs: Photonics/Optics

A proposed metrology system would be incorporated into a proposed telescope that would include focusing optics on a rigid bench connected via a deployable mast to another rigid bench...

Briefs: Electronics & Computers
Quasi-Optical Transmission Line for 94-GHz Radar

A quasi-optical transmission line (QOTL) has been developed as a low-loss transmission line for a spaceborne cloud-observing radar instrument that operates at a nominal frequency of 94 GHz. This QOTL could also readily be redesigned for use in terrestrial millimeter- wave radar systems and...

Briefs: Electronics & Computers

A method of utilizing information available in the constraints imposed by a low-density parity-check (LDPC) code has been proposed as a means of aiding the recovery of symbol...

Briefs: Electronics & Computers
The Interplanetary Overlay Networking Protocol Accelerator

A document describes the Inter - planetary Overlay Networking Protocol Accelerator (IONAC) — an electronic apparatus, now under development, for relaying data at high rates in spacecraft and interplanetary radio-communication systems utilizing a delay-tolerant networking protocol....

Briefs: Electronics & Computers
Group-III Nitride Field Emitters

Field-emission devices (cold cathodes) having low electron affinities can be fabricated through lattice- mismatched epitaxial growth of nitrides of elements from group III of the periodic table. Field emission of electrons from solid surfaces is typically utilized in vacuum microelectronic devices, including some...

Books & Reports: Physical Sciences
Progress in Acoustic Transmission of Power Through Walls

A document presents updated information on implementation of the wireless acoustic-electric feed-through (WAEF) concept, which was reported in "Using Piezoelectric Devices To Transmit Power Through Walls" (NPO-41157), NASA Tech Briefs, Vol. 32, No. 6 (June 2008), page 70. To recapitulate:...

Briefs: Software

A computer program performs Monte Carlo direct numerical simulations for testing sparse permutation channel codes, which offer strong error-correction capabilities at high code...

Briefs: Electronics & Computers

Electronic sensor systems for detecting and locating impacts of rapidly moving particles on spacecraft have been invented. Systems of this type could also be useful on Earth in settings in which the occurrence of...

Briefs: Electronics & Computers

Hollow-core, periodic bandgap (HCPBG) flexible waveguides have been proposed as a means of low-loss transmission of electromagnetic signals in the frequency range from about 300 GHz to 30 THz....

Briefs: Mechanical & Fluid Systems

An improved braking cable-payout mechanism has been developed. Like other such mechanisms, this mechanism can be used as a braking or shock-absorbing device for any of a variety of purposes — for...

Articles: Motion Control

Robotics technology has made measurable strides in the last few years. Today’s robots can move with greater precision over a more flexible range of motion, while handling heavier payloads....

Briefs: Semiconductors & ICs

A split-block waveguide circuit that rotates polarization by 90° has been designed with WR-3 input and output waveguides, which are rectangular waveguides used for a nominal...

Articles: Imaging

A chromatic or color-corrected lenses for use in the visible portion of the electromagnetic spectrum have been addressed in literature, textbooks, and industry journals as early as the 18th Century. Many...

Articles: Photonics/Optics

Communications and, more recently telecommunications, are needs deeply engrained in human history. These needs have significantly evolved over time enabling today’s content-rich (text, music, images and...

Briefs: Mechanical & Fluid Systems

Figure 1 depicts an experimental inchworm- type linear microactuator. This microactuator is a successor to the one described in "MEMS-Based Piezoelectric/ Electrostatic Inchworm Actuator" (NPO- 30672), NASA...

Briefs: Electronics & Computers

A four-port magic-T hybrid waveguide junction serves as the central component of a high-efficiency two-way power combiner circuit for transmitting a high-rate...

Briefs: Mechanical & Fluid Systems

Phase-oriented gear systems are differential planetary transmissions in which each planet gear has two sets of unequal numbers of teeth indexed at prescribed relative angles (phases). The figure illustrates an...

Briefs: Information Technology
Software Framework for Peer Data-Management Services

Object Oriented Data Technology (OODT) is a software framework for creating a Web-based system for exchange of scientific data that are stored in diverse formats on computers at different sites under the management of scientific peers. OODT software consists of a set of cooperating,...

Briefs: Software
PREDICTS

PREDICTS is a computer program that predicts the frequencies, as functions of time, of signals to be received by a radio science receiver — in this case, a special-purpose digital receiver dedicated to analysis of signals received by an antenna in NASA's Deep Space Network (DSN). Unlike other software used in the DSN, PREDICTS...

Briefs: Photonics/Optics

Two procedures have been devised for tuning a photonic filter that comprises multiple whispering-gallery-mode (WGM) disk resonators. As used here, “tuning” signifies locking the...

Briefs: Physical Sciences
Broadband Achromatic Telecentric Lens

A new type of lens design features broadband achromatic performance as well as telecentricity, using a minimum number of spherical elements. With appropriate modifications, the lens design form can be tailored to cover the range of response of the focal-plane array, from Si (400–1,000 nm) to InGaAs...

Briefs: Photonics/Optics

An improved method has been devised for controlling the DC bias applied to an electro-optical crystal that is part of a Mach-Zehnder modulator that generates low-duty-cycle optical...