Environmental Radio Noise Generated by Cities and Towns

由电灯开关、电脑、无线电及电视接收器等“附带”发射机发出的无线电噪音，以及由未经许可的低功率无线电设备(例如无线电话、车库门开启器等)发出的无线电噪音，会对无线电频谱的其他使用者造成严重的干扰问题。了解附带的和未经许可的辐射器所产生的噪声水平非常重要，例如对于减少干扰战略的规划、无线电观测站和其他通信系统的设计和选址也是如此。然而，对不同社区产生的噪音水平的测量几乎是不存在的。公安局建议在大约30至600兆赫的频率范围内，从飞机上获取此类测量数据。目前的建议是将去年提出的工作延长一年。这一延期将使私人投资者能够研究噪音水平的季节性和周期性变化，找出造成噪音的一些主要因素，并确定是否可以根据个别来源的知识来预测综合影响。

Radio noise generated by "incidental" transmitters such as light switches, computers, radio and television receivers, and by non- licensed low power radio devices, e.g. cordless telephones, garage door openers, etc. create serious interference problems for other users of the radio spectrum. Knowledge of the noise level generated by incidental and non-licensed radiators is important, for example for the planning of interference reduction strategies, the design and siting of radio observatories and other communication systems as well. Measurements of the noise level generated by different communities are almost non-existent, however. The P.I has proposed to obtain such measurements from aircraft, within the 30 to 600 MHz frequency range, approximately. The present proposal is for a one year extension of the work proposed last year. The extension will enable the P.I. to study seasonal and cyclical variations of the noise level, identify some of the main contributors to the noise, and determine if aggregate effects can be predicted from the knowledge of individual sources.