Direction finding electromagnetic lens antenna array
The main purpose to design an Antenna system with a low complexity based direction finding electromagnetic lens antenna array. By using micro strip patch antenna and 180 hybrid rat race ring coupler which generates ? and ? patterns of received RF signal and Electromagnetic Lens. The EM
2025-06-28 16:32:10 - Adil Khan
Direction finding electromagnetic lens antenna array
Project Area of Specialization Information & Communication TechnologyProject SummaryThe main purpose to design an Antenna system with a low complexity based direction finding electromagnetic lens antenna array. By using micro strip patch antenna and 180 hybrid rat race ring coupler which generates ? and ? patterns of received RF signal and Electromagnetic Lens.
The EM Lens provide the advantage of focusing the received signal energy on a small area subset of the antenna array, by taking the focusing ability to reduce complexity of ? and ? patterns to find the Direction of Arrival (DOA) of received Radio frequency RF signals.
The integration of lens enhances the direction finding antenna array by focusing the received signal energy on small area which means less number of antennas to receive signal energy through EM Lens which reduces hardware and computational complexity.
Therefore we will be integrating an Electromagnetic Lens, for the focusing or deflection of moving charged particles, such as electrons or ions. We combine Electromagnetic (EM) lens to reduce the complexity of the direction finding lens antennas array.
The focusing ability of the lens antennas can significantly contribute to perform low complexity in direction finding. Thus, by combining EM (electromagnetic) lens with antennas and coupler, we propose an approach for direction finding through direction/angle of arrival (AOA).
The development of EM lens is that to provide the advantage of focusing the received signal energy on a small area/subset of the antenna array at the base station (BS).We propose a complexity reduced sum (?) and difference (?) partner technique to find the direction of arrival (DOA) of the received radio frequency (RF) signals.
Direction of arrival (DOA) or Angle of arrival (AOA) estimation having application in radar, sonar, military, acoustic, communication and medical imaging, is frequency task in array signal processing. Although the existing related works about the direction finding in the lens antenna array can provide the desired result.
The propose is to address the direction finding application in a lens antenna array system with reduced hardware and computational complexity using the EM lens antennas. A simple direction finding approach that we refer to as sum-difference (? - ?) pattern detection scheme. The EM lens focuses the received signal energy on small area of the antenna array deployed at the BS, the ? - ? pattern detection scheme can be applied on the RF signals of these few excited antennas to find the DOA. As a result the process to reduce furthers the signal processing computation complexity for direction finding.
Initially we will start working on two-axis direction finding antenna system using sum-difference patterns in X-band, which consist of micro strip patch antenna array of two elements spaced 0.6? and 180 ? hybrid rat race coupler which generates ? and ? patterns of two received signals using software ‘Advanced Design System’(ADS) which operates on two axis or 2D. Later by using a software ‘Microwave Studio CST’ which is a CAD software built specially for the simulation of 3D Ems and antenna designing, also it is unique due to its support for designing components and filters that support propagation of higher frequencies and 3D design from CST will help us bringing simulation into fabrication.
Then we will simulate an Electromagnetic lens on CST. The focusing ability of the lens antennas can significantly contribute to perform low complexity in direction finding lens antenna array. Thus, by combining EM (electromagnetic) lens with antennas and coupler, we propose an approach for direction finding through direction/angle of arrival (AOA).
afterwards we will start fabrication of parts of direction finding electromagnetic lens. First we will start fabricating micro strip patch antenna array; later on we will fabricate coupler and electromagnetic lens. The development of EM lens is that to provide the advantage of focusing the received signal energy on a small area/subset of the antenna array at the base station. The last stage of the fabrication is the Integration of micro strip patch antenna, coupler and EM lens.
We analyzed a simplified system for radio source localization using an EM lens MAA. Firstly, we discussed the lens antennas system model and studied the focusing ability of the lens antennas as a function of the lens geometric parameters and angle of incidence. This focusing ability of the lens opens the door to localization systems based on MAA technology. This approach allows to simplify the system complexity with good performance results. Secondly, by combining the EM lens with a MAA, we will presented an approach for localization based on AoA estimation in multipath channels using a subsets/coupler based antenna selection, ToA estimation based FAP detection, and different AoA estimation algorithms. The localization results obtained by employing the EM lens are in good agreement to the conventional system w/o the lens with, however, significantly reduced complexity. Hence, the proposed approach has a great potential for application to next generation 5G wireless
Technical Details of Final DeliverableIn one and two-dimensional arrays consisting of identical linear antennas. A linear antenna elements, say along the z-direction, has an Omni-directional pattern with respect to the azimuth angle (ø). By replicating the antenna element along the x or y directions, the azimuth symmetry is broken. The proper choice of the array feed coefficient, any desired gain pattern g (ø) can be synthesized.
If the antenna element is replicated along the z-direction, then the Omni-directionally with respect to ø is maintained. With enough array elements, the prescribed polar angle pattern g (ø) can be designed.
The patch elements can be controlled by adding an extra indirect coupling path. The main aim of this work is to create a suitable extra coupling path that opposes the signal going directly from one radiating element to other.
In this we use ring coupler or 180 HRR coupler, consisting of four ports, it's mainly used in RF/microwave devices. The couplers and power dividers are fundamental passive circuit in wireless front ends to coupler the RF signals. Couplers can be incorporated with the balanced mixers, balanced power amplifiers, in antenna feed networks, measurement systems, and so on, for power coupling and equal or unequal power division in a desired way.
The advantage of being realized in planar technologies such as micro strip and strip lines using various techniques, such as the slow-wave artificial transmission lines, flooded micro strips, lumped elements.
If we apply the two input signals at two ports, we can obtain the difference (?) and sum (?) of these inputs at two other output ports. There are three common circuits of 180 hybrid couplers such as rat race coupler, wave guide hybrid junction, also known as magic-T, and tapered coupled-line hybrid. The most widely used among them is the HRR coupler.
We analyze the performance of a 180 HRR coupler through electromagnetic (EM) field simulation at different frequencies of operation and dielectric substrates. One antenna array, The coupler can be integrated with the micro strip patch antenna array consisting of two antenna elements in order to take ? and ? of the received signal to estimate the angle of arrival (AOA) of the received signal. The AOA estimation approach has the advantage of being realized in the RF domain which avoids the use of conventional and complex approaches that operate in base band (BB) and that require down-conversion hardware chain and digital processing. The performance is analyzed both via simulation and via experimental measurements using a fabricated coupler.
In this we discuss how the 180 HRR coupler can be integrated with the patch antennas array in order to obtain the ? and ? pattern from the two received signal samples and we combine Electromagnetic (EM) lens to reduce the complexity of the direction finding lens antennas array.
| Item Name | Type | No. of Units | Per Unit Cost (in Rs) | Total (in Rs) |
|---|---|---|---|---|
| Total in (Rs) | 156000 | |||
| PCB sheets | Equipment | 2 | 25000 | 50000 |
| SMA connectors | Equipment | 10 | 300 | 3000 |
| Lens material | Equipment | 1 | 10000 | 10000 |
| RF cables | Equipment | 5 | 1000 | 5000 |
| Stands | Miscellaneous | 2 | 5000 | 10000 |
| PCB sheets | Equipment | 2 | 25000 | 50000 |
| SMA connectors | Equipment | 10 | 300 | 3000 |
| Lens material | Equipment | 1 | 10000 | 10000 |
| RF cables | Equipment | 5 | 1000 | 5000 |
| Stands | Miscellaneous | 2 | 5000 | 10000 |