针对射频识别(RFID:Radio Frequency Identification)系统的信道资源有限,当多个标签竞争同一个频率或时间槽时,会导致发生碰撞和冲突的问题,为优化广播信道的通信效率,对基于帧时隙ALOHA的物联网RFID广播信道防碰撞算法进行了研究。该...针对射频识别(RFID:Radio Frequency Identification)系统的信道资源有限,当多个标签竞争同一个频率或时间槽时,会导致发生碰撞和冲突的问题,为优化广播信道的通信效率,对基于帧时隙ALOHA的物联网RFID广播信道防碰撞算法进行了研究。该方法引入帧时隙概念,对通信时间进行时间段划分;通过时隙内空闲、成功识别以及碰撞3种状态的发生概率分析,得到广播信道内的碰撞原因。结合贝叶斯算法与泊松分布规则,通过标签数目概率分布计算,实现读写器作用范围内标签数量的估计,并根据标签数量计算结果调整下一帧帧长。若调整后的帧时隙范围内仍存在标签碰撞问题,则通过FastICA(Indcpendent Component Analysis)独立主成分分析法,将帧时隙内的标签识别问题,转化为EPC(Electronic Product Code)编码生成问题,进而实现统一时隙内多标签的并行识别,避免发生碰撞。实验表明,所提方的标签数量的估算准确,能在保证通信信道稳定性的前提下,提高时隙内标签识别率,有效提高广播信道的传播效率。展开更多
This paper describes a multi-threat real-time separating system for broadband anti-radiation missile seeker. It presents a method, with a dual-port memory as comparer, to perform PF and PW hardware real-time separatio...This paper describes a multi-threat real-time separating system for broadband anti-radiation missile seeker. It presents a method, with a dual-port memory as comparer, to perform PF and PW hardware real-time separation and to determine the time-of-arrival (TOA) by use of sequential difference histogram (SDIF). The method has been applied to practice, which has achieved good results.展开更多
文摘This paper describes a multi-threat real-time separating system for broadband anti-radiation missile seeker. It presents a method, with a dual-port memory as comparer, to perform PF and PW hardware real-time separation and to determine the time-of-arrival (TOA) by use of sequential difference histogram (SDIF). The method has been applied to practice, which has achieved good results.
