Overview of method to reduce pilot overhead
Invention Summary:
Orthogonal time frequency space (OTFS) modulation provides reliable communication in high mobility environments and is a promising candidate for 6G, but existing approaches require large amounts of pilot overhead when transmitting. This wastes bandwidth as well as limiting scalability in multi-input multi-output (MIMO) devices since the guard regions must not overlap between antennas.
Rutgers researchers have created a novel approach for MIMO OTFS systems that significantly reduces pilot overhead by embedding pilots in the time-frequency (TF) domain and guard bins in both the DD and TF domains. The TF guard bins ensure exclusivity of pilots to their respective antennas, while the DD guard bins prevent the TF pilots and guard bins from interfering with the DD domain information. At the receiver, based on the symbols received on the pilot bins and also coarse estimates of the parameters of the scatterers that comprise the channel, a sparse signal recovery problem can be formulated, the solution of which provides the channel parameters. This method drastically reduces pilot overhead (0.006% versus 7% overhead for the same system) and is robust to Doppler shifts encountered in high-mobility scenarios. Compared to the overhead in non-overlapping MIMO channel state information (CSI) estimation, which is nearly 60% in a 2x1 MIMO system, this is a drastic reduction and allows scalability for future MIMO systems integrating this method.
Market Applications:
MIMO Devices
Next-gen wireless
Unmanned aerial vehicles (UAVs)
High-speed rail
Advantages:
Drastic reduction in pilot overhead (0.006% versus 7% overhead for same system setup compared to state-of-the-art existing methods)
Allows scalability to large MIMO systems
Robust against Doppler shifts in high-mobility scenarios
Pilots embedded within OTFS burst, enabling in-burst CSI acquisition with minimal overhead
Intellectual Property & Development Status: Provisional application filed. Patent pending. Available for licensing and/or research collaboration. For any business development and other collaborative partnerships, contact: marketingbd@research.rutgers.edu