Luca Petrillo

Theoretical and Experimental Investigation of a 60-GHz Off-Body Propagation Model

A fast computation and accurate analytical model for off-body propagation is derived in this paper. The paper discusses the off-body model propagation from an external source to a receiver located on the body. The model is developed for normal incident plane wave by describing the human body with a circular cylinder. We show that the total received electric field around the human body can be written as a creeping wave in the shadow region and as a geometrical optics result for the lit region. It is also shown that at 60 GHz, the shadow boundary width is negligible. The model shows perfect agreement with the experimental results conducted on a perfectly conducting cylinder. Measurements of the creeping wave path gain have been also conducted on a real body to assess the validity of the cylinder assumption. The results have shown a path gain of about 5 dB/cm for the TM case and 3 dB/cm for the TE case. The standard deviation between the measurements and the cylindrical model is about 3.5 dB for both TM and TE cases.

Analytical Creeping Wave Model and Measurements for 60 GHz Body Area Networks

The propagation of 60 GHz electromagnetic waves around a human body is studied analytically and experimentally. The body is treated here as a circular lossy cylinder, which is an approximation of the human torso. Analytical formulations based on creeping wave theory are given and discussed for both vertical and horizontal polarizations. An exact path gain expression is derived from analytical formulations and a simpler first order approximation is given. Path gain coefficients are shown for frequencies spanning the world available 60 GHz unlicensed band and for several sizes of the torso. Finally, the results of an experimental campaign conducted in an anechoic chamber to isolate the contribution of on-body propagation are reported. The measurement of the distance dependence of the received power on a brass cylinder and on a human body for both vertical and horizontal polarizations confirmed theoretical predictions.

Negative Permittivity Media Able to Propagate a Surface Wave

In the fleld of High Frequency Surface Wave Radar (HFSWR), this paper deals with a study which determines the electric permittivity and conductivity values that a medium must hold to propagate a sole surface wave at its interface with air. Firstly, we demonstrate clearly the reason why the Zenneck Wave cannot be excited on sea surface. Kistovich decomposition is used for this purpose. Secondly, the reasoning is extended to identify electric permittivity and conductivity values that permit to excite a surface wave on an homogeneous medium. Finally, numerical validation is obtained by comparison with the analytic formulation of the fleld radiated by a vertical Hertzian dipole as it has been established by Norton.

Statistical On-Body Measurement Results at 60 GHz

This communication studies the path loss and shadowing between two body mounted devices at 60 GHz. The temporal fading is experimentally investigated and the Doppler spectrum is characterized and modeled. Measurements have been conducted in an anechoic chamber for both horizontal and vertical polarizations.

Creeping Wave Model of Diffraction of an Obliquely Incident Plane Wave by a Circular Cylinder at 60 GHz

This paper presents a creeping wave model for the diffraction of an obliquely incident plane wave by a perfectly conducting or lossy circular cylinder at 60 GHz. The model developed for both TM and TE polarizations is valid for electrically large cylinders and for a receiver in the close vicinity of the surface. An experimental validation is conducted on a perfectly conducting cylinder.

Performance Assessment of IR-UWB Body Area Network (BAN) Based on IEEE 802.15.6 Standard

Performance of impulse radio-based ultrawideband (IR-UWB) communications in wireless body area networks is investigated using the dedicated IEEE 802.15.6 standard. An IR-UWB transceiver system is implemented for both on-off keying and differential binary phase-shift keying modulations. Bit error rates are determined from measurements for different on-body links with different data rates. It is shown that using a 25-dB-gain low noise amplifier (LNA) at the receiver, reaching an uncoded bit error rate BER of 10-3 was not possible for some links operating at higher data rates. Power and energy consumption issues are then addressed, and results in terms of required pJ/bit to achieve a certain quality of communication are given and discussed.

TDOA estimation method using 60 GHz OFDM spectrum

In the field of high data rate wireless communications, localization issues play a key role in achieving energy-efficient communication and geographic routing. time-difference of arrival (TDOA)-based localization methods present numerous advantages. In this paper, a new method of TDOA estimation is proposed. With this method, unlike conventional TDOA measurements, it is possible to perform communication and localization at the same time by using a multi-input single-output system. By transmitting ultra-wide-band orthogonal frequency-division multiplexing signals using spatial diversity, it is possible to extract TDOA from interference patterns in spectral domain. In addition, increasing the precision of localization is also studied using a multi-band approach. This whole study is made within the framework of the WiGig alliance specifications; however, it is compatible with other standards.

UWB Interferometry TDOA Estimation for 60-GHz OFDM Communication Systems

A simple technique to estimate the time difference of arrival (TDOA) that necessitates only one reference device to perform 1-D positioning of a mobile device is presented. Using a multiple-input-single-output (MISO) system, this interferometric technique uses ultrawideband signals and is particularly well suited for 60-GHz orthogonal frequency-division multiplexing (OFDM) communications. The accuracy of the technique is assessed by simulation, using the IEEE 802.11ad channel, as well as by measurement.

Information Spatial Focusing Scheme for UWB Wireless Communications in Smart Environments

This letter presents an information spatial focusing method for future smart environments using ultrawideband (UWB) wireless communications. This method allows to send high-data-rate information at predetermined specific spatial positions without localizing users, thereby protecting their privacy. The proposed approach is a combination of simplified UWB beamforming and signal processing. Compared to classical UWB beamforming, the proposed method exhibits greater information focusing capabilities by increasing greatly the peak-to-floor ratio between main and side beams.

A 60 GHz Off-Body channel implementation

In the field of smart environments, high data rate wireless wireless communication can be reached with the unlicensed 60 GHz RF Band. In this spectrum, Body Area Networks channel modeling is required. In this paper, a 60 GHz Off-Body channel modeling is presented using a simplified and fast computation result of the scattering of plane waves by a human body at 60 GHz and the IEEE 802.11ad indoor channel model.