Speaker
Description
Distributed RF systems have become increasingly relevant in recent years due to the rapid growth of technologies such as cell-free massive MIMO, satellite communication networks, and the Internet of Things, due in part to major benefits in adaptability and scalability. For such systems operating at microwave and millimeter-wave frequencies, it is often necessary for these distributed platforms to be strictly aligned in time, frequency, and phase to ensure high performance; however, this induces significant clock distribution system architecture challenges where nodes are not connected with any wires as typical low-frequency coupling of reference oscillators between platforms is not possible.
In this talk, we outline a high-accuracy fully digital wireless coordination technique based on high-precision sub-sample time-of-arrival estimation for wirelessly coordinated coherent distributed antenna arrays using software-defined radio platforms. First, we will describe the theory underpinning the method and illustrate how to compensate for skews in timing, frequency, and phase across distributed platforms. Further, we will illustrate the need for high-speed update rates for such wireless compensation based on in-lab measurements and introduce our implementation of latency-reduction techniques using hardware compute accelerators (e.g., FPGA or GPU) to meet these goals. Additionally, we present an experimental evaluation of this approach in comparison with a traditional CPU-based implementation, to illustrate potential performance improvements of such coordination for phase-sensitive operations like distributed phased array beam scanning.
| Talk Length | 30 Minutes |
|---|---|
| Acknowledge | Acknowledge In-Person |