Faskalibrering i storskaliga distribuerade antennsystem

This project will explore fundamental limits and develop practical techniques for phase alignment in distributed antenna systems.

In such systems,  a potentially large number of geographically separated antennas (access points) are to cooperate phase-coherently on some task, for example, beamforming in wireless communications. For phase-coherent operation to work, the access points need to have an accurate, common phase  reference.

We are specifically concerned with the  phase alignment over-the-air, using bidirectional, over-the-air measurements between pairs of access points.

The project consists of four tasks: (i) fundamental limits on scalability of over-the-air phase alignment in networks with many access points; (ii) how to integrate access-point-to-access-point calibration measurements with data transmission (beamforming) into the TDD flow in a wireless distributed antenna system; (iii) models that learn behaviors of the local oscillators (frequency references) and track their phase; (iv) application-specific performance analyses of performance for distributed MIMO, over-the-air data aggregation, distributed relaying, and positioning.