论文研究-基于正交变换的负载调制信号解调方法.pdf

所需积分/C币:14 2019-07-22 19:36:23 664KB .PDF
收藏 收藏
举报

在装定器接收到的负载调制信号中,载波信号与反馈信号相位相差π/2,且前者幅度远远大于后者,因此,负载调制信号的调幅度接近于1,用包络检波方式难以解调出反馈信号。提出了一种正交变换方法,可以简便地实现载波信号的正交变换,使得载波信号与反馈信号同相,增强负载调制信号的幅度变化率,从而降低反馈信号的提取难度。随后采用了Simulink软件完成正交变换方法的仿真系统的设计,验证了该方法的可行性和有效性。
第11期 熊东,等:基于正交变换的负载调制信号解调方法 4233 可计算出,在ωL1=51Z1,y=1/4的条件下,正交变换 前Aa/Am=0.9806,故q=1.94%;正交变换后Amn/Am 结束语 0.833,故n=16.7%。通过正交变换将幅度变化率η提高了 本文针对包含引信装定信息的负载调制信号调幅度接近于 个数量级,大大提高检波出的调幅信号的强度,有利于降低 ,难以用包络检波方式解调的冋题,提出∫一种可以増强负载 负载调制反馈的振幅键控信号的提取难度。 调制信号的幅度变化率的正交变换方法。通过采用本方法,可 在载波频率为13MHz,y=114,,1=5|Z|条件下 以将与反馈信号U正交的载波信号U转换成与反馈信号U 反馈数据分别为0和1时,发射端的电感测试电压信号x(1)同相的U,在L1>>E的条件下,可以提高携带引信反馈信 波形和正交变换后的信号n(1)波形的仿真图如图4所示。息的负载调制信号幅度变化率m达到10倍以上,提高了检波出 图4(a)为反馈数据为0的波形:上方波形为正交变换前a2()的调幅信号的强度降低负载调制反馈信号的提取难度。 的波形;下方波形为u(t)正交变换后的波形。图4(b)为反 参考文献: 馈数拼为1的波形:上方波形为正交变换前u,(t)的波形;下方 [1]马宝华.现代引信的控制功能及特征[J].探测与控制学报, 波形为u,(t)正交变换后的波形 [2]CHRISTIAN K Improvements in operational distance in passive HF RFID transponder systems[ C//Proc of IEEE International Confe rence on RFID( Frequency Identification ) 2008: 350-357 [3 JIANG Bing. Energy scavenging for inductively coupled passive RFID systems[ C]//Proc of IE F.E. Instru mentation and Measurement Tech nology Conference, 2005: 984-989 4 CHAIMANONART N, KO W H, YOUNG D J Remote RF powering (a)数据0时,变换前后 b)数据1时,变换 system for MEMS strain sensors C//Proc of Technic al Digest, IEEE 电压波形对比 前后电压波形对比 International Conference on Sensors. 2004:1522-1525 图4正交变换前后电压波形对比图 由仿真图可知如果直接对(以包络检波方式解调,数5]周东,张河用于引信的能量和信息非接触同步传输技犬[ 字信号为0和1时对应的信号幅度变化很小,很难提取出信号 兵工学报,2003,24(3):424-426 m(t);经正交变换后的m′,(t)在数宇信号为0和1时幅度变化 [6]张峰.基于副载波的负载诩制技术实现引信感应装定信息反馈的 方法[冂.探测与控制学报,2003,25(2):16-19 大大増强,可用很简单的包络检波方式解调出传输信号。表1 I7 ZANGL H, BRETTERKLIEBER T H. Demodulation of 13. 56 MHz 为ωLZn为不同数值时,正交变换对负载调制信号增强效果 load-modulated signals J. Elektrotechnik Informationstechnik 的定量计算值(y=1/4)。 2007,124(11):364-368 表1正交变换前后信号幅度变化率 [8 FINKENZELLER K RFID H and book[ K]. German: John Wiley o L/Zrl 变换前的T 变换后的1 2003:67-70 19.4×10-3×100% 16.7×10-2×100% [9 TANG Zheng-nian, SMITH B Data transmission from an implantable bio- 4.68×10-3×100% 6.82×10-2×100% telemetry by load-shift keying using circuit configuration modulator[J] 2.08×10-3×100% 4.69×10-2×100% IEEE Trans on Biomedical Engineering, 1995, 42(5): 524-528 1.7×10-3×100%3.57×10-2×100% [10] PROAKIS J C Digital communications[ M]. 4th ed. Beijing: Publish 0.749×10-3×100%2.88×10-2×100% ing House of Electronic Industry, 2003: 1 86-202 (上接第4230页) schemes in large scale sensor networks[C]//Proc of the 9th Annual [2 BAHL P, HAN NP. RADAR: an in-building RF-hased user location International Conference on Mobile Computing and Networking. 2003 and tracking system[ C]//Proc of the 19th Annual Joint Conference of the IEEE Computer and Communications Societies Proceedings. T [7 SHANG Yi, RUML W, ZHANG King, et al. Localization from mere Aviv. IEEE Press. 2000: 775-784 connectivity C//Proc of the 4 th ACM International Symposium on [3] SAVARESE C, RABAEY JM, BEUTEL J Location in distributed Ad Mohile Ad hoc Netwarking and Computing. 2003: 201-212 hoc wireless sensor network C//Proc of IEEE International Confe- [8 COSTA J A, PATWARI N. Distributed multidimensional scaling with rence on Acoustics Speech and Signal. 2001 adaptive weighting for node localization in sensor netw orks[ J]. ACM Trans on Sensor Networks, 2006, 2(1): 39-64 [4 BULUSU N, HEIDEMANN J, ESTRIN D GPS-less low cost outdoor [9 PATAWI N, PERKINS M, CORREAL N S, et al. Relative location es- localization for very small devices[ J. IEEE Personal Communica- timation in wireless sensor network[J. IEEE Trans an Signal Pro tions Magazine, Special Issue on Smart Spaces and Environ cessing, Special Issue on Signal Processing in Networks ments,2000,7(5):28-34. 2003,51(8):2137-2148 15 DOHERTY L, GHAOLI L E, PISTER K S J Convex position estima 10 RAPPAPORT T S. Wireless communications: principles and pracLice tion in wireless sensor networks[ Cl//Proc of the 20th Annual Joint I MI.2nd ed.S1.: Pearson Education, 2001: 121 Conference of the IEEE Computer and Communications Societies. [11 DEMPSTER A P, LAIRD N M. RUBIN D B. Maximum likelihood es- 2001:1655-1663 timation from incomplete data via the EM algorithm[ J] Journal of [6 HE Tian, HUAN Cheng-du, BLUM B M, et al. Range-free localization the Royal Statistical Society, Series B, 1978, 38(1): 1-38

...展开详情
试读 3P 论文研究-基于正交变换的负载调制信号解调方法.pdf
立即下载 低至0.43元/次 身份认证VIP会员低至7折
    抢沙发
    一个资源只可评论一次,评论内容不能少于5个字
    上传资源赚积分,得勋章
    最新推荐
    论文研究-基于正交变换的负载调制信号解调方法.pdf 14积分/C币 立即下载
    1/3
    论文研究-基于正交变换的负载调制信号解调方法.pdf第1页

    试读已结束,剩余2页未读...

    14积分/C币 立即下载 >