摘要
文中介绍了VDES系统中数据段的译码方法,数据段采用8PSK或16QAM调制的Turbo编码。译码方法分两步,第一步是将8PSK或16QAM调制的符号软判决逆映射恢复成软信息,软信息通过计算对应信息比特的似然对数比得到;第二步是将获得的软信息送入到Turbo译码器进行译码。通过Matlab仿真,得到不同调制方式数据段的比特误码率曲线。VDES系统标准中规定了系统正确工作需要的最低信噪比,采用不同调制方式的数据段正确工作的最低信噪比也不相同。在对应信噪比下,将仿真得到的误码率与VDES系统标准中规定的误码率作比较可知,仿真得到的误码率满足标准要求,说明此译码方法可行。
The decoding method of the data segment in the VDES system is introduced.The data segment uses 8PSK or 16QAM modulated Turbo encoding.The decoding method is divided into two steps.The first step is to restore the soft decision reverse mapping of 8PSK or 16QAM modulated symbols to soft information.The soft information is obtained by calculating the likelihood logarithmic ratio of the corresponding information bits.The second step is to send the obtained soft information to the Turbo decoder for decoding.Through Matlab simulation,the bit error rate curves of data segments with different modulation methods are obtained.The VDES system standard specifies the minimum signal⁃to⁃noise ratio required for the correct operation of the system,and the minimum signal⁃to⁃noise ratio for the correct operation of data segments with different modulation methods is also different.Under the corresponding signal⁃to⁃noise ratio,the simulated bit error rate can be compared with the bit error rate specified in the VDES system standard.The simulated bit error rate meets the standard requirements,which means that the decoding method is feasible.
作者
王硕同
王建新
WANG Shuotong;WANG Jianxin(School of Electronic and Optical Engineering,Nanjing University of Science and Technology,Nanjing 210094,China)
出处
《电子设计工程》
2021年第9期29-34,共6页
Electronic Design Engineering
