Patent ID: 6822574
Filing Date: 2004-11-23
Classification: G01S,H04B,Y02A

Abstract:
An ionosonde comprising:a signal-transmitting section configured to transmit to an ionosphere pulsed radio waves whose frequency is scanned; a signal-receiving section comprising a loop antenna system configured to measure intensity of a magnetic field Hz of pulsed radio waves reflected by the ionosphere, a first dipole antenna system configured to measure an intensity of an electric field Ex orthogonal to the magnetic field Hz and a second dipole antenna system configured to measure an intensity of an electric field Ey orthogonal to the magnetic field Hz and electric field Ex; and a signal-processing section configured to use three intensity values obtained at the signal-receiving section to obtain a cosine (nx, ny) of an arrival direction {right arrow over (n)} of the reflected radio waves in accordance with relationship nx=(HzEx*âˆ’ExHz*)Z/(ExEy*âˆ’EyEx*) and relationship ny=(HzEy*âˆ’EyHz*)Z/(ExEy*âˆ’EyEx*), wherein Z stands for intrinsic impedance, and Ex*, Hz*, and Ey* are the conjugate complex numbers of Ex, Hz, and Ey, respectively.