Low cost product authentication for counterfeit protection

据估计，全球每年因假冒产品而造成的损失约为1万亿美元。尽管如此，认证产品的市场规模相当小。这在一定程度上是由于缺乏制作和读取认证标签的完全令人满意的方法。目前还没有广泛使用的标签。我们最近开发了一种微型磁强计，它同时具有高灵敏度和廉价的特点。我们已经演示了它区分来自不同来源的简单标记的能力。为此，我们利用了基波和二次谐波巨磁阻抗信号的变化。我们还对二次谐波信号和基波噪声进行了理论和实验研究。我们在这里建议开发一种新型的数字标签，它也应该是廉价的，可以在一小块软磁带或微线中存储大量难以伪造的信息，并且可以使用微型磁强计读取，该微型磁强计将针对二次谐波信号的读取进行优化。这种第二代标签可能会提供一个重要的市场机会。

Losses due to counterfeiting of products are estimated to be $1 trillion annually worldwide.  Despite this, the market for authentication products is quite small. This is partly due to the lack of fully satisfactory methods for making and reading authentication tags. There are no labels in widespread use. We have recently developed a micro-magnetometer which is at the same time highly sensitive and inexpensive. We have demonstrated its ability to distinguish simple tags from different sources. For this purpose, we use changes in both the fundamental and second harmonic giant magnetoimpedence signals. We have also been conducting theoretical and experimental studies of the second harmonic signal and of noise in the fundamental. We propose here the development of a novel digital tag, which should also be inexpensive, and which can store considerable information, difficult to counterfeit, in a small piece of soft magnetic ribbon or microwire, and which can be read using the micro-magnetometer, which will be optimized for reading of the second harmonic signal. This second-generation tag could provide an important market opportunity.