Method and Apparatus for Encoding and Decoding Dirty-Paper-Coded Nested-Lattice Codes

Computing & Wireless : Wireless and Communications

Available for non-exclusive licensing


  • Sriram Vishwanath, Ph.D. , Electrical and Computer Engineering
  • Sang Hyun Lee , Electrical and Computer Engineering
  • Sung-Soo Hwang , Samsung Electronics Company, Ltd.
  • Sang Boh Yun , Samsung Electronics Company, Ltd.

Background/unmet need

The broadcast channel is one of the most fundamental entities in multi-user information theory. For the multiple antenna Gaussian broadcast channel, it is now well known that “dirty-paper ” coding achieves the entire capacity region. However, one of the biggest stumbling blocks for this channel has been the impracticality of dirty-paper coding. First, dirty-paper coding requires accurate knowledge of the channel state information for all the channels at the transmitter; and second, even with the state known, it is exponentially complex to perform the encoding and decoding process required by traditional dirty-paper coding mechanisms. Results for cellular networks have shown that dirty-paper coding can have large gains over approximate strategies, and thus it is essential that a low-complexity mechanism of performing it be determined.

Invention Description

This invention is a practical way of encoding more than two messages simultaneously on a multiple antenna downlink of a wireless channel. This system operates at capacity of the multiple antenna downlink, meaning that there is no loss in performance when using this encoding scheme. It also operates at an average complexity that is polynomial in time, thus making it the only known practical coding strategy that achieves capacity in a multiple antenna downlink in wireless network.


    Saves power consumption and accelerates data processing for dirty-paper processing.


  • Invention includes a method to construct nested lattice codes that allow dirty paper encoding and decoding for broadcast communications.
  • The multiple nested lattice codebooks are chosen for each of the multiple receivers. Once a lattice codebook is constructed, the next lattice codebook for another receiver is constructed by simple scaling off the previous lattice codebook.

Market potential/applications

Low-power and wideband mobile broadcast devices using MISO communication

IP Status

  • 1 foreign patent application filed