Orthogonal code for polarization angle division diversity

Abstract

The polarization angle diversity uses different angle regions of the polarization to transfer a signal that is multiplied by the special codes in these regions. These special codes have both local and global orthogonalities and are cyclic because the entire region is 360 degrees. The entire code and independent parts of this code both have very weak mutual correlation to their cyclic shift and each other to achieve the global and local orthogonalities. The orthogonal balanced code is proposed as a candidate for this special code. Both the local and global orthogonalities of the proposed code are numerically examined by comparing them with the two codes that are based on M-series. The numerical results indicate that the proposed code not only has both strong local and global orthogonalities but also shows the frequency spectrum whose occupied bandwidth and peak value are respectively very narrow and low. These characteristics ensure usefulness of the code for the polarization angle diversity.