一种低功耗自适应地球物理勘探数据传输方法的研究

With the development of electronics, the scale of geophysical exploration is bigger and bigger, Sercel and WesternGeco are turning the mega channel seismic into fact. But the battery technology which is used to supply the power for such equipment grows slowly. The power consumption for a big equipment is more critical than for a small one. Base on the research experience, the power requirement for the data transceiver is one of the main part of the total system. There are lots of equipment employ some mature industry communication protocol such as RS485, LVDS etc., which lead high power consumption. Only dedicated circuits can lower the power, we get the conclusion after the research of design of UniQ. Based on the fact which could affect the power requirement and the characteristics of the geophysical exploration data transmission, we propose an adaptive and low power transceiver which is optimized for geophysical exploration data transmission. The preliminary experimental result shows the plan is reasonable. If we could make success as we desired, we can lower the power consumption of a data acquisition station to the level of 508 from Sercel and UniQ from WesternGeco, which is about 100mW.

地球物理勘探随着电子技术的发展在向着大道数方向迈进，Sercel和WesternGeco等公司正在把前些年还在概念阶段的百万道地震勘探设备逐步变为事实。然而用于这些野外设备供电的电池技术却远落后于电子技术的发展。如果说小型设备还不太考虑功耗问题的话，大型设备往往可能会因功耗超标被一票否决。根据以往项目的经验，数传是影响站体功耗的重要因素。在很多设备开发中采用的RS485、LVDS等工业标准总线，虽取得了一定的实用效果，但同508、UniQ等系统的功耗参数比起来仍有较大的差距。只有专用设计才能有效降低功耗，这是在研究了UniQ等一些系统结构后得到的启示。本项目从影响数据传输功耗的几个基本因素出发，结合地球物理勘探数传的特点，提出了一个可自适应动态调整数传功耗的方法。初步的实验数据表明该方法是基本可行的，如果能够成功，采用这种方法的采集站，其功耗将降低到与UniQ基本持平的100mW左右。

在基金委的资金资助下，按照预定计划进行了低功耗自适应地球物理勘探数据传输方法的研究。项目从影响数据传输功耗的几个基本因素出发，结合地球物理勘探数传的特点，提出并实现了一个可自适应的动态调整数传功耗的方法。实验数据表明该方法在降低数传功耗方面起到了很大的提升，它能够在小道距（10-50米）的条件下，且数据率在4.096Mbps时，使得一对收发器的功耗小于3mW。以此为基础，实现了采集站整体功耗不高于80mW的设计，达到并超过了基金的预期目标。这样的功耗基本上和Sercel的508或者WesternGeco的UniQ系统在同一水平。除上述任务书中的研究内容外，还进行了地震勘探数据压缩的研究，采用了指数求导的哈夫曼编码技术，使得在保持数据误差低于千分之一的情况下，达到了48%的压缩率。数据压缩不仅可以进一步降低数据传输部分的功耗，还可以减轻后端数据存储的压力。