CASSEGRAIN TYPE DUAL-REFLECTOR ANTENNA CALCULATION METHOD

Предложен способ расчета двухзеркальной антенны Кассегрена, отличающийся введением виртуального дополнительного облучателя для повышения точности расчетов направленных свойств и шумовой температуры. Приведен пример расчета антенны. A method for calculating a two-reflector Cassegrain antenna is proposed, characterized by the introduction of a virtual additional irradiator to increase the accuracy of calculations of directional properties and noise temperature. An example of the antenna calculation is given.

BI-QUAD DUAL REFLECTOR ANTENNA FOR WLAN TASKS

Рассматривается двухрефлекторная Bi-Quad антенна, способная работать в диапазоне частот, соответствующих WLAN Wi-Fi 2,4 ГГц. Благодаря возможности управления положением рефлекторов удается добиться изменения направления излучения, что повышает эффективность использования антенны, коэффициент направленного действия. При управлении происходит поворот ячеек, из которых сформированы отражательные структуры, что позволяет пропускать электромагнитное излучение, которое формирует излучатель из медного провода в форме цифры «восемь». Предложенная конструкция позволяет обеспечить три стабильных режима работы антенны: двустороннее излучение, когда оба рефлектора в открытом положении, при таком режиме у антенны наблюдается одинаковое излучение в обоих направлениях с равным КНД; излучение вверх, в данном режиме верхний рефлектор открыт, что приводит к свободному протеканию электромагнитных волн, а от закрытого нижнего происходят отражения, в результате этого происходит увеличение КНД антенны по сравнению с ситуацией двустороннего излучения; аналогичная ситуация происходит при излучении вниз, когда открыт нижний рефлектор, так электромагнитные волны отражаются от закрытого верхнего рефлектора вниз, что приводит к увеличению КНД антенны. Предложенная конструкция обладает высокой эффективностью в диапазоне рабочих частот The article discusses a two-reflector Bi-Quad antenna capable of operating in the frequency range corresponding to WLAN Wi-Fi 2.4 GHz. Thanks to the ability to control the position of the reflectors, it is possible to achieve a change in the direction of radiation, which increases the efficiency of using the antenna, and increases the directivity. During control, the cells are rotated, from which the reflective structures are formed, which allows the transmission of electromagnetic radiation, which is formed by the emitter, formed from a copper wire in the shape of the number "eight". The proposed design makes it possible to provide three stable modes of antenna operation: double-sided radiation, when both reflectors are in the open position, in this mode the antenna has the same radiation in both directions with equal directivity; radiation upward, in this mode, the upper reflector is open, which leads to free flow of electromagnetic waves, and reflections occur from the closed lower reflector, as a result of this, the antenna directivity increases in comparison with the situation of two-sided radiation. A similar situation occurs when radiating downward, when the lower reflector is open, so electromagnetic waves are reflected from the closed upper reflector downward, which leads to an increase in the antenna directivity. The proposed design is highly efficient in the operating frequency range

Methods of Electrodynamic Modelling for Reflector Antennas

The article discusses methods for calculating the electromagnetic characteristics of reflector antennas based on the finite integration method, the method of moments, and the hybrid method. In the course of the study, a performance comparison of these methods in the process of calculating the reflector antenna characteristics was made. Comparison of the calculation efficiency was carried out using four computing devices. On the basis of the calculations, the graphs of the scattering matrix and the directional diagrams of the antenna under study were obtained

Amplification of High Quality of Signal Strength Using Corner Reflector Antenna for Satellite Communications

The strengths of the corner reflector antenna (CRA) which spans space's dynamic pseudo-random phase wave-front, which can be used in frequency modulation of the echo, replacing doppler's typical style. Radiometric assumes that Imaging discoveries can change lives a kind of special geosynchronous in geostationary orbit for the extremely low SNR in this geometry, just have a very low signal to noise ratio (SNR) posit the use of such a matched filter to strengthen the SNR and enable the existence of good specificity. In this paper, the signal is amplified to send a high-quality signal to the transmitter for satellite communication using a corner reflector antenna. Apart from other antennas, the corner reflector antenna plays an important role in increasing the signal strength in satellite communication. Using this corner reflector antenna the system will be good and fast so that the transmitter or the receiver can transmit or receive the signal very fast. While transmitting the signal the noise or interference in the system can be eliminated for that reason the corner reflector antenna is used. The corner reflector antenna can reduce the system noise or interference so that the system will be in proper condition to transmit or receive the signal.

Performance Enhancement of Reconfigurable Metamaterial Reflector Antenna by Decreasing the Absorption of the Reflected Beam

In this study, a new concept for a Ka-band 5G communication tunable reflector metasurface (MS) for beam steering at 28 GHz is proposed. Varactor diodes are used as the tunability component of each unit cell of this MS. Significant improvements in beam steering and bandwidth performance were achieved using this new concept referred to as the stripes configuration. Several different geometries of unit cells arranged in stripes were designed to achieve better performance in directionality, gain, sidelobe level (SLL), and bandwidth in the stripes configuration. Simulation results for a three-stripe MS with different unit cells in each stripe showed better performance in the phase dynamic range and reduced reflectance losses compared to a typical one-stripe MS. The simulation results showed a significant improvement of 3 dB, depending on the steering angle in reflectance gain, compared to a uniform MS (one stripe). Furthermore, a significant improvement of approximately 50% in the accuracy of the steering angle for different operating frequencies was demonstrated. Manufacturing considerations are discussed in this study.