In this paper, the Contiguous Partition Method (CPM) is applied to the optimization of the directivity of difference patterns in monopulse planar array antennas. Since the excitations providing maximum directivity of planar arrays can be analytically computed and because of the excitation matching nature of the CPM, the problem at hand is recast as the synthesis of the difference compromise sol...

An ultrasonic transducer is a key component to achieve ultrasonic imaging. This paper designs a new type of Microelectromechanical Systems (MEMS) based capacitive ultrasonic transducer and a linear array based on the transducer. Through directivity analysis, it can be found that its directivity is weak due to the small size of the designed transducer, but the directivity of the designed linear ...

s Deadline 22 February 2010 Full papers due30 May 2010 Sydney is without a doubt one of the most beautifulcities in the world with a reputation for friendly people,a cosmopolitan lifestyle, wonderful shopping and world-class entertainment. The conference will be held atConvention & Exhibition Centre right at the edge of themagnificent harbour and within a short walk of t...

A single high-directivity microstrip patch antenna (MPA) having a rectangular profile, which can substitute a linear array is proposed. It is designed by using genetic algorithms with the advantage of not requiring a feeding network. The patch fits inside an area of 2.54 x 0.25, resulting in a broadside pattern with a directivity of 12 dBi and a fractional impedance bandwidth of 4 %. The ante...

Probabilistic seismic hazard analysis [PSHA, e.g., Cornell (1968); Anderson and Trifunac (1978); McGuire (1977); McGuire (1995)], typically used in risk assessment and hazard mitigation, has so far relied on ground motion prediction equations (GMPEs), also called attenuation relations [e.g., the next generation attenuation relations or NGA by Campbell and Bozorgnia (2008); Chiou and Youngs (200...

According to some compilations, the Laguna Salada, Baja California, earthquake of 23 February 1892 ranks among the largest earthquakes in California and Baja California in historic times. Although surface rupture was not documented at the time of the earthquake, recent geologic investigations have identified and mapped a rupture on the Laguna Salada fault that can be associated with high probab...

This paper proposes a new methodology to design optimal antennas for MIMO (Multi-Input Multi-Output) communication systems by using spherical mode expansion. Given spatial channel properties of a MIMO channel, such as the angular profile at both sides, the optimal MIMO antennas should provide the largest channel capacity with a constraint of the limited implementation space (volume). In designi...

The horizontal acoustic backscattering strength of a fish school is an important factor for fisheries and for estimation of the size of a fish school using omnidirectional scanning sonar. However, the backscattering strength of a fish school is influenced by their behavior and orientation because the individual fish in the fish school have strong directivity of target strength. This paper discu...