CRLB-based antenna selection for angle of arrival estimation
(2025)
Files
CRLB-Based Antenna Selection for Angle of Arrival(MA).pdf
Open Access - Adobe PDF
- 2.26 MB
Details
- Authors
Arash, Masoud 
- Supervisors
- Abstract
- (en) The new generation of wireless systems aim to bring a breakthrough of innovations in connectivity and smart communications. The ever growing need for higher data transfer and digitization of cities require new technologies to use available resources in the most efficient way. This creates an important question: How can new technologies be leveraged to design and implement sustainable telecommunication systems? Cellular networks, in which a fixed location base station serves a wide range of wireless devices, are the backbone of new generation of wireless systems. The base stations of such networks have to operate within several strict regulations and restrictions, due to environmental concerns related to global warming. The improvements of these networks to utilize their available resources like energy and hardware in an efficient way, play a key role in transformation toward a green communication network. This PhD research focuses on energy efficiency improvement and resource allocation challenges within a Multiple-Input Multiple-Output (MIMO) wireless network. In this regard, the localization phase of a wireless network, that aims to achieve location information of user devices, will be the main focus of this work. In the first part, the Cramer Rao Lower Bound (CRLB) for the angle of arrival estimation in a Multi-User Massive MIMO with linear antenna array when the received signals are accompanied by multipath signals is studied. It is demonstrated that irrespective of the distribution of multi-path signals the CRLB converges toward a deterministic value. Then, by using the obtained formulation for CRLB, a modified comprehensive version of energy efficiency in such networks in the localization phase is proposed and optimized with respect to the utilized antenna set at the base station. The optimal number of antennas to maximize the energy efficiency of the localization is presented, as well as the optimal approach to select the required number of antennas. In the next part, we extend the CRLB analysis to planar antenna arrays in multi-user massive MIMO systems and explore antenna selection strategies for such arrays. After acquiring the CRLB formulation for a planar antenna array in a multi-user scenario, it is shown that CRLB's formulation is a combined function of AoA, that needs the (unknown) AoA's value for optimization. To overcome this problem, the expected CRLB is chosen as the criterion of antenna selection. A greedy algorithm with an optimal starting point is proposed that aims to minimize the expected CRLB. Finally, in the last part of this thesis, we propose a real-time CRLB based antenna selection strategy whose objective function is to minimize the CRLB of a user in planar antenna arrays. First, we improve the antenna selection strategy that aims to minimize expected CRLB, from a greedy approach to an optimal analytical method. Then, we use this method to develop a two-step antenna selection strategy that aims to directly minimize the AoA CRLB of a user and further reduce the impact of unknown AoA on the selection process. In the second step of proposed antenna selection, a greedy algorithm is used with an optimal starting point whose performance is shown to be very close to the global search method.
- Affiliations
Citations
Arash, M. (2025). CRLB-based antenna selection for angle of arrival estimation [I E E E]. https://hdl.handle.net/2078.5/277318