Patents by Inventor Arumugam Nallanathan

Arumugam Nallanathan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6728295
    Abstract: This invention discloses a code division multiple access communications system based on spread sequences designed by using complete factorization of polyphase matrix of a perfect reconstruction (PR) filter bank. The key characteristic is that the length of the spread sequence is longer than the period of the data symbol i.e., the data symbols are spreaded by the spread sequence and overlapped with neighboring data symbols. The design method includes an orthogonal code generator, a number of cascading stages and random permutation matrices. The number of cascading stages and random permutation matrices are selected according to the length of the spread sequence required. The length of the spread sequence could be selected according to the system performance requirement, hence the overlapping factor of spreaded data symbols. Furthermore, this spread sequence assumes integer values instead of binary when the orthogonal code generator generates a Walsh-Hadamard code.
    Type: Grant
    Filed: June 30, 2000
    Date of Patent: April 27, 2004
    Assignee: University of Hong Kong
    Inventors: Arumugam Nallanathan, Tung Sang Ng, Shing Chow