We deal with the problem of modelling a radiator/ scatterer using an equivalent radiator. The amounts at determining shape and size radiating surface producing, on region D , electromagnetic field close to that generated by primary radiator/scatterer. For fixed radiator’s shape, we here dimensi...

A large-solid-angle, Cherenkov detector beam loss monitor has been built and tested as part of the Linac Coherent Light Source machine protection system (MPS). The MPS is used to protect the undulator magnets by detecting high-energy electron beam loss. These electrons produce other forms of radiation that can lead to demagnetization of the undulator magnets. Cherenkov light is generated when p...

We discuss the effects of particle correlations on the spectral broadening due to the radiator motion (Doppler broadening) for a Ni-like XUV laser line pumped in two different regimes (transient and quasi-steady state regimes) of collisional excitation. In a medium with gain, radiative transport effects modify the observed profile and these modifications depend on the homogeneous or inhomogeneo...

Two microstrip fed ultra-wideband (UWB) antennas with different band rejection techniques are presented in this paper. The designed antennas consist of a defected ground plane with an elliptical slot and two different radiator shapes. The first design is composed of a half circular ring radiator element while the second one uses a crescent shaped radiator. The radiators are fed by a 50 Ω micros...

Two distinct phenomena shape our planet: more than half of the world’s human population is urbanised (World Watch Institute 2007); and global warming induced climate change is a grave threat. Modern cities, in ecological terms, have become parasitic energy and resource ‘sinks,’ consuming 75% of the world’s resources on only 2% of the global land area (TFPC 1999). In this way cities ‘short-circu...

This chapter focuses on the design of compact planar multiband antennas intended for exist‐ ing wireless services including LTE, GPS, GSM, PCS, DCS, GPS, UMTS, WLAN and Wi‐ MAX bands. The present techniques available in the open literature include the modification of the main radiator via bending, folding, meandering and wrapping. Each approach offers different advantages, depending on the requ...

The profiles of spectral lines of a radiator (atom or ion) immersed in a plasma are a valuable diagnostic tool [1]. Under certain conditions [1, 2], the observed line shapes are closely related to the electric microfield distribution (MFD) at the position of the radiator [2]. Since the pioneering work of Holtsmark [2], various theoretical approaches to determine the MFD have been proposed. Most...

An antenna is a device that is used to transfer guided electromagnetic waves (signals) to radiating waves in an unbounded medium, usually free space, and vice versa (i.e., in either the transmitting or receiving mode of operation). Antennas are frequency-dependent devices. Each antenna is designed for a certain frequency band. Beyond the operating band, the antenna rejects the signal. Therefore...

We present experimental data towards the development of a low-order model for the jet noise source for predictions of isolated and installed noise. In the proposed scheme, the source is prescribed on a radiator surface defining the boundary between the inner rotational jet flow and the outer linear pressure field. The source consists of wavepacket-type partial fields whose noise emission can be...