# 通信·网络·安全先进技术研讨会：通信传输专场

In this talk, we determine the weight distributions of two classes of primitive BCH codes $\mathcal C_{(q, m, \delta_2)}$ and $\mathcal C_{(q, m, \delta_3)}$ and their extended codes, which solve two problems proposed by Ding, Fan, and Zhou. It is shown that the extended codes $\overline{\mathcal C}_{(q, m, \delta_2)}$ have four nonzero weights. We also employ the Hartmann-Tzeng bound to present the minimum distance of the dual code $\mathcal C_{(q, m, \delta_2)}^\perp$ for $q \ge 5$. Inspired by the idea, we then determine the dimensions of a class of cyclic codes and give lower bounds on their minimum distances, which is greatly improved comparing with the BCH bound. This is a joint work with Peng Wu and Fengmei Liu.

Multiple access technology played an important role in wireless communication in the last decades: it increases the capacity of the channel and allows different users to access the system simultaneously. However, the conventional multiple access technology,as originally designed for current human-centric wireless networks, is not scalable for future machine-centric wireless networks.

In this talk, we shall introduce sequences with optimal global and local correlation, and their applications in communications and radar.