Self-Trigger for Radio Detection of UHCR
Self-Trigger for Radio Detection of UHCR
复制标题
用于 UHCR 无线电检测的自触发
DOI：
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发表时间：
2009
期刊：
影响因子：
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通讯作者：
H. Falcke
中科院分区：
文献类型：
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作者：
A. Schmidt;H. Falcke
在用于宇宙线射电探测的大规模天线阵中，触发机制是关键特征之一。在要求低触发阈值以获得最佳事件接受的同时，每个站的触发速率必须足够低以允许无线通信的有限容量。此外，还需要低功耗，因为这些站将由太阳能供电。我们已经开发了一种触发算法，在FPGA硬件实现，提供了一个射频抑制通过傅立叶变换的无线电信号活频域，消除单频载波和变换回时域。这将信噪比提高了2倍。然后，应用阈值，并对特定脉冲形状参数进行切割，以进一步降低触发率。最后建立相邻天线之间的重合，并读出事件。目前的硬件开发和测试测量的第一个结果与3个原型天线的状态。
In a large scale antenna array for the radio detection of cosmic rays the trigger mechanism is one of the key features. While calling for a low trigger threshold for best event acceptance, the trigger rate of each station must be low enough to allow for the limited capacity of wireless communications. Additionally a low power consumption is required, as the stations will be solar powered. We have developed a trigger algorithm realized in FPGA-hardware which provides an RFI-suppression by Fourier transforming the radio signal live to frequency domain, eliminating mono-frequent carriers and transforming back to time domain. This improves the signal to noise ratio by a factor of 2. Then a threshold is applied and cuts on particular pulse shape parameters are performed to further reduce the trigger rate. Finally the coincidence between neighboring antennas is built, and the event is read out. The current status of the hardware development and first results of test measurements with 3 prototype antennas is presented.