The design of a 0.1, four-terminal current shunt with calculable frequency dependence up to 1 MHz is described. It is intended for use as a standard for current measurements up to 10 A rms with the primary purpose of being able to tie alternating-current measurements to direct-current measurements. The shunt is of the bifilar flat-strip configuration where the effects of self-inductance, skin effect, capacitance, dissipation factor, and eddy-current losses are considered. Contributions of the individual effects, where applicable, are determined by calculation based on geometry and...

Wireless communications are essential to emergency responders. Unfortunately, a typical emergency response scenario involves communication into and within building structures, which can severely interfere with or completely block the radio frequency channel. Several methods offer some potential relief to these problems, including the use of multi hop ad hoc networks for communication within the building, and the use of smart antenna arrays at exterior locations to improve the communication between the interior and exterior locations of the building. However, due to the enclosed nature of...

This is the second in a series of NIST technical notes (TN) on propagation and detection of radio signals in large buildings before, during, and after implosion. The first NIST TN (NIST TN 1540) described a similar experiment carried out on a 13-story apartment building in New Orleans, LA. These data will give first responders a better understanding of what to expect from the radio-propagation environment in disaster situations. The goals of this work are two-fold: (1) to create a large, public-domain data set describing the attenuation in various building types of radio signals in public...

Certain antennas on the market today are used for electromagnetic compatibility measurements such as radiated immunity and emissions testing. These are designed to cover a broad frequency spectrum while maintaining specified directional properties. However, trying to meet both criteria leads to distortion either in the phase or amplitude properties of the incoming signal. Designing an antenna with desired qualities in the time-domain will translate to an antenna with a broadband response in the frequency domain.

The provision of calibration services (or measurement services in this document) is an essential element of the work of the Sources, Detectors, and Displays Group (as part of the Electronics and Electrical Engineering Laboratory). In the conduct of this work, as in all its efforts, the group is committed to excellence that is characteristic of a global leader in measurements and standards. Our goal is to provide measurement services that meet the needs of our customers and, through continuous improvement, to anticipate their needs, exceed their expectations, and deliver outstanding value to...

The design and performance of a Next Generation Sampling Comparator Probe (NGSCP) is described. It is intended as one of a group of probes designed for use with the NIST Sampling Waveform Analyzer (SWA). The probe design is centered on an application specific integrated circuit (ASIC) analog comparator featuring a bandwidth of 6 GHz. The design considerations of the ASIC analog comparator and the probe are discussed. The probe's performance features are compared against a previously designed ASIC probe. In addition to the design aspects of the probe, a thermal error correction technique is...

The Field Parameters and EMC Applications Project of the National Institute of Standards and Technology (NIST) has recently completed shielding effectiveness studies of three representative aircraft for the Federal Aviation Administration (FAA). These studies will be used to provide the FAA with the procedures and data reduction techniques for typical low-level airframe penetration for high intensity radiated field (HIRF) attenuation/shielding tests.

Some time ago, what is now the Electromagnetics Division of the National Institute of Standards and Technology (NIST) developed the capability to measure noise parameters of amplifiers 1,2]. Recently, modified methods and analysis have been developed and have been applied both to amplifiers 3] and to transistors 4], the latter in an on-wafer environment. For such measurements to be meaningful, the results must be accompanied by corresponding uncertainties.

Several years ago, a project was begun under the auspices of the Committee on Earth Observation Satellites, Calibration and Validation Working Group, to compile standards definitions for terms used in microwave remote-sensing radiometry.

This publication is the second Part in a series of Recommendations regarding modes of operation of symmetric key block ciphers.