Multiple-access code generation

Reference Number: K 05-02

Inventors: Dyer, Justin; Natarajan, Balasubramaniam

USPTO Link: 7587660

Invention Summary

The present invention may be used to potentially improve wireless data and other communication systems. When wireless transceivers operate in an environment with many reflectors, received signals may arrive from different paths. This condition is known as multipath. Wireless transceivers may utilize multiple antennas to exploit multipath for increasing the communications bandwidth. For example, in some embodiments, wireless transceivers may communicate using Multiple-Input-Multiple-Output (MIMO) techniques. In general, MIMO systems offer higher capacities by utilizing multiple spatial channels made possible by multipath.

The invention may adapt an asymptotically optical decoding algorithm to provide for constructing and/or updating a precoding matrix in a MIMO system. For example, this invention may employ a trellis-exploration algorithm similar to a Viterbi algorithm.

Advantages

• Flexible precoder matrix dimensions

• Sub-array processing

• Multiple levels of Quality of Serice

• Allow for system overloading

• Optimized for minimum processing complexity (for real-time applications), rapid updates, low power consumption, and/or low cost processing components

Applications

The invention is not limited to particular types of communication systems. For example, the invention may be implemented within:

• Wireless LAN

• Wi-Max

• Waveguide

• Optical free space

• Ultra-Wideband systems

• Remote-sensing systems (Radar, Lidars, RF tagging, and sensor networks)

The invention may be configurable for generating precoder matrices, updating precoder matrices, and/or reassigning subchannel codes in response to demand for network resources, changes in the number of users accessing the network, individual user-access requirements, changes in signal-propagation characteristics (e.g., multipath, Doppler, path loss, ect.), and/or interference (e.g.; ISI, MAI, jamming).