Purpose. To increase the speed of correlation-interferometric direction finding. Simplification of the data processing algorithm and, accordingly, increased performance. Possibility of direction finding in real time without increasing the discreteness error
Specifications.
- Operating frequency range (50-6000) MHz.
- SLE bearing mark: does not exceed 1 degree.
- Bandwidth of direction finder radio receivers: 10 MHz.
- Sampling frequency of received radio emissions at intermediate frequency: 32 MHz.
Application area. Radio engineering and robotics, analogue manufacturers: Rohde & Schwarz, LSTelcom (Germany); “TCI”, “Agilent Technologies”, “ADVANTEST” (USA); “Thaies” (France); “AOR”, “ISOM” (Japan); “Winradio” (Australia); TOB KHSVD-2 “Spetsvuzavtomatika” (Ukraine, Kharkov), as well as the State Concern “Ukroboronprom”, State Enterprise “Ukrainian State Radio Frequency Center”.
Advantages. Compared to existing technologies: 1) Direct one-time correlation latency estimation. 2) There is no need to use a multi-channel data processing system or introduce a huge discrete error in estimating the delay time. Advantages for consumers of the developed technologies: the possibility of real-time simultaneous monopulse correlation direction finding of all radio emission sources falling within the wide bandwidth of the direction finder will allow you to quickly draw up a map of the sources of all radio emission; – direction finding of weak and noisy radio emissions at long range due to the low (0 dB) required input signal-to-noise ratio; – high accuracy of direction finding; the ability to upgrade modern direction finders by replacing software and antennas.
Technical and economic effect. Consists of improving the technical characteristics of the equipment and reducing its cost. Increased profits from equipment sales. An important expected effect from the introduction of scientific results into modern radio monitoring tools is a significant increase in their performance due to the ability to provide real-time simultaneous correlation direction finding of all radio sources falling within the wide bandwidth of the direction finder. This will allow you to quickly map the sources of all radio emissions in the frequency range 20 MHz – 6 GHz and above, and will increase the competitiveness and volumes of products sold due to its exclusive parameters and capabilities. Cost reduction occurs by reducing the computational complexity of signal processing algorithms and using less productive computer equipment.
Description. The receiving antennas are located at an antenna base distance from each other. For direction finding, the following is carried out: 1. Simultaneous reception of the signal by the first antenna in the first direction-finding radio channel and the signal by the second antenna in the second direction-finding radio channel. 2. Estimation of time spectra of received signals using FFT. 3. Multiplication of the selected spectra of two direction-finding radio channels to form the first product of the spectra. 4. Formation of two subarrays of spectral samples from the first product of spectra. 5. Multiplication of the first and second subarrays of spectral samples to form the second product of spectra. 6. Maximum likelihood non-search (direct) correlation estimate of signal delay time. 7. Based on a certain estimate of the delay time, the direction to the source of radio emission is estimated. To estimate the bearing in a 360-degree sector, it is necessary to estimate the bearing in relation to two perpendicular antenna pairs. You can use a 3-channel radio receiver.