点对点信道与两用户广播信道并存时的自由度

Degrees of Freedom of Coexistence Network with Point-to-Point and Two-user Broadcast Channels

研究了两个网络并存时的自由度:一个网络是点对点(PTP)信道,另一个网络是两用户的广播信道(BC)。根据两个网络之间可能存在的消息认知情况,考虑了4种系统模型:次网BC对主网PTP发送端无消息认知、次网PTP对主网BC发送端无消息认知、次网BC对主网PTP发送端有消息认知、次网PTP对主网BC发送端有消息认知。运用干扰对齐和干扰消除的方法对干扰进行了干扰管理,分析了可达自由度,并给出了自由度的外界。通过比较4种情况,发现当主网是PTP、次网是BC且次网认知主网发送端消息时获得的自由度区域最大。

The degrees of freedom（DoF）of two networks with coexistence was investigated in this paper.One is a point-to-point（PTP）channel and the other is a two-user broadcast channel（BC）.Four system models were considered.First,BC as se-condary network is not cognitive of PTP（primary network）transmitter＇message.Second,PTP as secondary network is not cognitive of BC transmitters＇ messages.Third,BC as secondary network is cognitive of PTP transmitter＇message.Fourth,PTP as secondary network is cognitive of BC transmitters＇ messages.The achievable DoF was obtained by using interference alignment and interference neutralization.Besides,the outer bound was proven.Compared with the other three system models,the achievable bound is biggest when BC as secondary network is cognitive of PTP transmitters＇ message.