A Method For Ionospheric Oblique Sounding By Means Of Array Receiving

Ionospheric physics is a subject combining theoretical research with experiments. Ionospheric sounding has been playing an important role in the ionospheric research. It has been shown from the ionospheric development history that the new sounding techniques or methods always strongly promote the development of ionospheric physics research. At the same time,the ionospheric physics research also requires more new sounding techniques and methods. In the history of nearly 80 years development of ionospheric sounding,the ionospheric oblique sounding is a significant content since it is very important to understand the process of radio-wave propagation in the ionosphere.A new receiving system for ionospheric oblique sounding is developed in the paper. It can receive several oblique sounding signals which not only have the same frequencies but also have the different direction of arrivals on an array antenna simultaneously. A technique on array signal mono-channel processing and norm-weighted Capon beam-forming algorithm for direction estimation is proposed to improve the output gain of the system and the capability of suppressing interference. Finally , a method of maximum likelihood is used to estimate the amplitude,phase,time delay and doppler shift of the oblique sounding signal.We only do some research in the method for ionospheric oblique sounding by means of array receiving. Of course,we will meet many questions what will occur later. We hope that the paper could give some new ideas for the application of array signal processing in ionospheric oblique sounding.