This study presents the idea of using GPS-output velocity signals to obtain wave measurement data. The application of the transformation from a velocity spectrum to a displacement spectrum in conjunction with the directional wave spectral theory are the core concepts in this study. Laboratory experiments were conducted to verify the accuracy of the inversed displacement of the surface of the se...

This paper presents an element of a 2×2-element array antenna for Inmarsat BGAN/GPS applications. The element is an axial mode printed quadrifilar helical antenna that has been integrated with a compact feed network to provide sequential phase rotation for circular polarization (CP) radiation. The novel integrated lumped-element feed network is designed to provide a balanced RF power to the fou...

Radio frequency interference (RFI) is one of the foremost concerns in safety critical applications that utilize GPS. RFI sources either intentional or unintentional at the vicinity of the victim receiver can potentially mask the weak GPS signals. Most commercial receivers are equipped with no or basic level of protection against in-band RFI. Acquisition under strong RFI is more difficult as the...

A dual-band circularly polarized antenna fed by four apertures that covers the bands of GPS, Galileo, is introduced. The ARSAs designed using FR4 substrates in the L and S bands have 3-dB axial-ratio bandwidths (ARBWs) of as large as 37% and 52%, respectively, whereas the one using an RT5880 substrate in the L band, 61%. In these 3-dB axial-ratio bands, impedance matching with VSWR<=1.8 is also...

In this paper, wide band balanced antenna with enhanced bandwidth performance that covers the 850 to 3000 MHZ of Band, covering the GSM, UMTS, Bluetooth, GPS, & Wi-Fi applications is investigated[1-4]. This antenna was designed in HFSS which have low profile, linear phase and constant radiation pattern with proper return loss and resonant on multiple frequencies. This proposed antenna was then ...

A new global positioning system (GPS) antenna is proposed to cover the three GPS bands (L1, L2, and L5, namely 1575, 1227, and 1176 MHz) with the L5 band to be added after 2006. The developed antenna size is only 1 5 1 5 in aperture corresponding to 7 7 ( = free space wavelength) and 13 thick. Quadrature feeding is employed to ensure right-hand circular polarized (RHCP) radiation. The final min...

The Global Navigation Satellites Systems (GPS, GLONASS and the future GALILEO) has proven to be a useful tool for precision deformation monitoring applications in structural engineering. For continuous structural deformation monitoring on an epoch-by-epoch basis it is desirable for a measurement system to deliver equal precision in all position components, all the time. However, the quality of ...