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Measurements of radio signal leakage from a building at 821 MHz and 2.193 GHz are presented. It is shown that the COST231 outdoor-to-indoor building penetration model is suitable for predicting this leakage. Indoor locations that give the best indication of leaked power are also identified. These are important if indoor cognitive radio transmitter powers are to be controlled dynamically by an indoor sensor network. Signal strength at indoor locations near the building walls exhibits high correlation with the leaked power. [ABSTRACT FROM AUTHOR]

Neural signal propagation is completely different from electron transport in conventional electronic devices. The electrical control of propagation of a neural signal in a single neuron is interesting from the standpoint of neural device applications in future, which could be the basis of future pain control or activation of a neuron in a part of the body. In this reported work the control of neural signal propagation in a single neuron has been successfully achieved using the three terminal electrodes method. By using 'soma' the transport of the neural signal in a neuron has been completely shut down. This complete shutdown of the transport of the neural signal makes it possible to fabricate new neural logic circuits including switching of the neural signal in a neuron. [ABSTRACT FROM AUTHOR]

Reported are the results of a coherence bandwidth experimental investigation of broadband propagation measurements for future millimetre-wave WLANs. Based on a sweeping-frequency sounding technique (59.6-60.6 GHz), the channel coherence bandwidth (Bc) is estimated in two typical indoor environments: (a) a 20 m, non-line-of-sight (NLOS) T-shaped corridors intersection, with and without the presence of a transmission route deflecting obstacle (DO), and (b) a line-of-sight (LOS) empty conference room. Results demonstrate thats millimetre-wave communications are very sensitive to the propagation environment. Thus, precise information of phases and amplitudes across the band of interest are essential for accurate estimation of the channel Bc. Results also indicate that the NLOS millimetre-wave environments are very hostile and the presence of DOs might enhance significantly the millimetre-wave propagation characteristics including the channel Bc. [ABSTRACT FROM AUTHOR]

The objective of this reported work was to characterise electromagnetic wave propagation between adjacent rooms in the lower deck areas of ships. A wideband multiple-input multiple-output channel sounder has been used to realise double directional propagation measurements at 2.2 GHz. The antenna configuration was a linear array at the transmission side and a rectangular one at the reception. The measurement data are first processed with a classic beamforming technique, then with a high resolution algorithm to extract the dominant paths. A ray-tracing based simulation tool is used to understand the measurement results. It is observed that, in spite of the metallic structure of watertight doors, wireless communication remains possible between adjacent rooms after door closure. Results show that electromagnetic waves mainly propagate through door edges openings. [ABSTRACT FROM AUTHOR]

An iterative technique for improving the temporal focusing of a time reversal mirror is proposed and tested. A single amplification parameter is introduced to tune the convergence of the iteration. The tunable iterative technique has been validated by tests on an experimental electromagnetic time reversal mirror, as well as on a novel numerical model. [ABSTRACT FROM AUTHOR]

Depth maps play an important role in 3DTV applications for rendering stereo views. Most existing automatic algorithms cannot generate an acceptable quality of depth maps from a mono-channel video sequence. Proposed is a key-frame depth propagation algorithm, combining trilateral filtering to produce high-quality depth sequences. Experiment results show that the algorithm outperforms a well-known prior work in terms of depth PSNR by up to 3.5 dB. [ABSTRACT FROM AUTHOR]

In the open literature on the geometric modelling of wireless radiowave landmobile propagation channels, this reported work is the first to attempt to account for the propagation power loss of the multipaths, in deriving closed-form expressions for an uplink received-signal's spatial-correlation-coefficient function across the aperture of a base-station antenna-array. [ABSTRACT FROM AUTHOR]

The wave propagation inside a periodic cut-wire array is investigated. The effective propagation constant is extracted from numerical simulation and measurement. Both the plasmonic cutoff behaviour and the cut-wire resonance are presented and analysed. [ABSTRACT FROM AUTHOR]

The fabrication and propagation loss measurement of GaAs/polymer optical nanowires are reported. Their design consists of a 300×300 nm cross-section GaAs core buried into a polymer matrix bonded on a Si host substrate. The propagation loss at λ=1.55 µm is measured as about 5 dB/mm for both polarisations. [ABSTRACT FROM AUTHOR]

A new way to experimentally simulate propagation channels between antenna arrays using coupled mode-stirred reverberation chambers is presented. This technique, which can be performed in a laboratory facility, is simple to use and allows the easy modification of the channel characteristics. [ABSTRACT FROM AUTHOR]

Reports on mutual coupling effects between antenna elements on signal correlation. Derivation of a simple expression to compute the correlation coefficient from the far-field radiation patterns including the characteristics of the propagation environment and the terminating impedance; Demonstration that the mutual coupling between closely spatially separated dipoles can lead to increased signal decorrelation.

Presents group velocity, vg, dependence of propagation loss in single-line-defect photonic crystal waveguides on GaAs membranes, and minimum loss as low as 2.5 dB/mm. Observation that when vg is reduced by a factor of 7, an additional loss is found to be only 5 dB/mm, thus proving a feasible usage of low vg.

A propagation experiment using a uniform linear array at the base station in rural and suburban areas is presented. Wideband parameters, cluster behaviour and angular parameters at the base and mobile stations are analysed. Statistical results are provided and typical situations presented. [ABSTRACT FROM AUTHOR]

The transmission characteristics of two waveguides, one carrying a forward, the other a backward magneto-inductive wave, are investigated. The experimental results obtained are compared with the theoretical predictions. It is shown that there is excellent agreement for the frequency dependence of the propagation coefficients and good agreement for the attenuation coefficients. [ABSTRACT FROM AUTHOR]

Planar line-defect photonic crystal waveguides with a weak vertical refractive index contrast (substrate-type) suffer from large propagation losses in the order of 600-1000 dB/cm. A possibility to reduce propagation losses is to optimise the vertical layer stack for a given hole shape. This strategy is pursued to reduce the propagation losses numerically and experimentally. It is demonstrated that the loss figure can vary by a factor of about 2 for relatively small changes in the core layer thickness. [ABSTRACT FROM AUTHOR]

A compact substrate integrated coaxial line (SICL) 3 dB coupler is proposed, designed, fabricated and measured. Compared with some available reports of substrate integrated waveguide 3 dB couplers, this SICL coupler maintains good performance but with a remarkable 80% reduction in size. [ABSTRACT FROM AUTHOR]

Presented is the statistical analysis of radio wave propagation in a high-speed railway cutting scenario, derived from 930 MHz measurements taken along the 'Zhengzhou-Xi'an' high-speed railway of China. The crown width and bottom width of the cutting are well-covered by the proposed models. The Ricean distribution offers a good fit and the K-factor is found to be lognormal, with a mean value of 1.88 dB and standard deviation of 3.29 dB. [ABSTRACT FROM AUTHOR]

A 2.5 Gbit/s burst-mode receiver with power-level burst-detection and a time-critical control circuit is presented. With its unique topology, this receiver is successfully operated as a long-reach XG-PON1, where the quiet-window for ranging operation exceeds the time variation of the round-trip propagation delay for up to 40 km. [ABSTRACT FROM AUTHOR]

A novel zigzag microstrip slow-wave structure is presented, which effectively reduces the occupied length to 34% of a normal microstrip structure. A sample power divider using the slow-wave structure is given, the whole size of the proposed divider has been reduced by 39% compared to a conventional power divider. The design is validated both by simulation and by measurement. [ABSTRACT FROM AUTHOR]

Using the reverberation chamber to obtain antenna radiation efficiency is considered. The reverberation chamber, which has for many years been used for electromagnetic compatibility measurements, can also be used with great advantage for antenna measurements since it simulates effectively a uniform multipath propagation environment. How a reverberation chamber can be used to measure the ultra-wideband (UWB) antenna efficiency in a very short time is described. The procedure based on time domain is described and some experimental results are given and compared to measurements obtained by the Wheeler cap method extended by Schantz to UWB antennas. [ABSTRACT FROM AUTHOR]

Adaptation of QoS in DWDM optical networks routing and the wavelength assignment (RWA) problem, known as an NP-hard problem, are addressed. The QoS constraint based routing RWA computes lightpaths for the original-destination node pair, (O, D), to meet the QoS propagation delay requirements. A heuristic algorithm based on a genetic algorithm (GA) is then developed to solve this problem. A simulation program is developed to demonstrate the efficiency of the GA for the COST 239 network. The trade-off between the capacity and the propagation delay has been analysed. Results show that the trade-off is 8.7% of the average capacity, increasing to 10.6% decrease for the average delay. [ABSTRACT FROM AUTHOR]

Theoretical aspects and experimental results are presented for beam-forming techniques operating on an array of HF collocated antennas without the need for space diversity. This original application achieves the separation of two propagation modes associated with a given path on the ionospheric channel. A specific device, based on different types of active antennas, has been developed and experimental results validate this concept. [ABSTRACT FROM AUTHOR]

The beam-propagation method is applied to the analysis of a bent light-guiding metal (Ag) line loaded on an embedded dielectric core. For a bending radius of down to ≅ 200 μm, the propagation loss is found to be smaller than that of a straight metal line at a wavelength of 1.55 μm. [ABSTRACT FROM AUTHOR]

Results of modelling square-wave propagation along coupled coplanar transmission line with grounded centre strip conductor are presented. Improved agreement between numerical and experimental data for the near- and far-end crosstalk voltages has confirmed practical significance of inclusion of multimode propagation in non-ideally grounded coplanar lines. [ABSTRACT FROM AUTHOR]

The modified uniformly most powerful belief-propagation (UMP-BP) decoding algorithm is proposed. This utilizes a new normalization factor to diminish the error introduced by approximation of the soft values. The proposed algorithm shows better performance than the normalization UMP-BP algorithm, and has the same complexity of implementation. [ABSTRACT FROM AUTHOR]

Presents the novel design of the circular polarization (CP) for an annular-ring antenna operated at its TM11 and TM12 modes. Indication that the CP radiations of the proposed design are achieved by placing an L-shaped strip connected to two orthogonal sides of the inner boundary of the annular patch; Observation that broadside radiation patterns with good CP characteristics can be obtained at the two operating resonant modes.

Proposes a single-feed triangular microstrip patch antenna that can be operated at two distinct resonant modes. Ability of the two resonant modes to radiate an omnidirectional dipole-like pattern with linear polarization and a broadside pattern with circular polarization, respectively; Study of several designs of the proposed antennas with different substrate thickness and patch sizes to achieve the required frequency ratio of the two operating frequency bands.

Simulation results for the capacity distribution of an indoor multiple input multiple output (MIMO) communications system are presented. Results are based on ray traced propagation data for micro- and macro-MIMO array configurations. Capacity levels are compared with well-known mathematical results for uncorrelated Rayleigh fading. Significant capacity gains are seen using a macro-MIMO configuration. [ABSTRACT FROM AUTHOR]

A theoretical multi-slope wave propagation model is proposed based on ultra-wideband radio channel impulse response measurements in a dispersive channel. The theory, which applies to radiowave and acoustic propagation, relates multipath delay spread, propagation attenuation exponent, and the maximum possible rake gain for the multipath propagation channel. [ABSTRACT FROM AUTHOR]

Watertight metallic doors are no barrier to installing wireless networks inside a ship, according to researchers at the Institute of Telecommunications of Rennes (IETR), France. In their Letter published in this issue of Electronics Letters, they experimentally demonstrate how radio leakage between metallic adjacent rooms separated by watertight doors is of a sufficient level for communication between network nodes in a wireless sensor network (WSN). This result is another step towards a cost-effective wireless solution for future shipboard monitoring systems. [ABSTRACT FROM AUTHOR]