CAJ | 학술논문

近年来面向时差估计的数据压缩成为信号处理领域的研究热点之一。类似基于传感器网络时差定位的应用场景，要求运用实用化的数据压缩技术，以降低平台设计和实现的难度，同时在数据传输量和时差估计精确度之间取得较好折衷。利用窄带通信信号在被子带抽取压缩后，时差估计克拉美罗界最低的子带基本对应信噪比最高的子带这一特点，将复杂的基于费舍尔信息量最大化的压缩准则合理地简化为基于离散傅里叶变换幅值平方和最大化准则，以提高压缩效率，同时为降低有限观测时间的影响，提出一种频点抽取结合子带抽取的压缩方法。最后经仿真验证，在压缩比不变的前提下，提出的改进数据压缩方法相比单纯的子带抽取法明显提高了时差估计精确度，在信噪比大于0 dB 的情况下，通过仅传输和利用128个频点信息，可以实现几十纳秒量级的时差估计精确度。
근년래면향시차고계적수거압축성위신호처리영역적연구열점지일。유사기우전감기망락시차정위적응용장경，요구운용실용화적수거압축기술，이강저평태설계화실현적난도，동시재수거전수량화시차고계정학도지간취득교호절충。이용착대통신신호재피자대추취압축후，시차고계극랍미라계최저적자대기본대응신조비최고적자대저일특점，장복잡적기우비사이신식량최대화적압축준칙합리지간화위기우리산부리협변환폭치평방화최대화준칙，이제고압축효솔，동시위강저유한관측시간적영향，제출일충빈점추취결합자대추취적압축방법。최후경방진험증，재압축비불변적전제하，제출적개진수거압축방법상비단순적자대추취법명현제고료시차고계정학도，재신조비대우0 dB 적정황하，통과부전수화이용128개빈점신식，가이실현궤십납초량급적시차고계정학도。
In recent years,data compression for Time Difference of Arrival(TDOA) estimation has become the hotspot in the signal processing field. Application field like emitter location using TDOA based on sensors network requires practical data compression technology,which can reduce the difficulty of platform design and implementation,and get a trade-off between the data amount for transmission and the accuracy of TDOA estimation. The compression rule based on maximizing Fisher Information is simplified to which based on maximizing the sum of the squared discrete Fourier transform magnitude,and the efficiency of data compression is improved,according to the feature that sub-band with lowest TDOA estimation Cramer-Rao Bound has the highest signal to noise ratio generally after the narrow-band communication signal being compressed by sub-band extraction. The sub-band extraction method is developed by combining with frequency extraction in order to reduce the effect of limited observing time. Simulation results show that,the proposed measures can obtain much higher accuracy of TDOA estimation than sun-band extraction method under the same compression ratio;tens nanosecond order of TDOA estimation accuracy can be achieved by transmitting and utilizing only 128 frequency points under signal to noise ratio above 0 dB.