Impedance Controllable Microwave Mesh for Reducing Human Field Exposure in Handheld Communication Devices

在没有移动电话服务的偏远地区，卫星通信是唯一可行的选择。为了实现可靠的低地球轨道通信信号水平，比如铱星系统，可能需要地面发射天线辐射出相当大的功率。这使得在手持消费产品中很难达到最大允许的人体电磁场暴露水平。Solara远程数据传输公司是一家加拿大公司，设计、制造和销售手持卫星通信设备。Solara正在开发一种附加模块，这将使他们的手持设备适应用户的智能手机。Solara需要开发一种天线系统，当手持设备放置在用户附近时，该系统将减少现场暴露水平，同时仍能获得可接受的信号。Solara正在与曼尼托巴大学高级射频系统实验室的Greg Bridges博士合作开发一种自适应系统，该系统将通过监测发射天线的阻抗变化来检测用户的存在，然后引导天线发出的辐射远离用户的身体，以减少磁场暴露水平。自适应天线系统将解决Solara将这种新型产品推向市场的主要挑战之一。一种可以接入铱星系统的手持式智能手机附加模块有可能给Solara的卫星手机技术带来竞争优势。它将为偏远地区的用户提供可靠的通信手段，对加拿大北部地区很重要。

In remote areas where cellular service is not available satellite communications is the only viable option. To achieve a reliable signal level low Earth orbit communications, such as the Iridium system, may require the ground based transmitting antenna to radiate a substantial amount of power. This can make adherence to maximum allowed human electromagnetic field exposure level difficult to achieve in a consumer handheld product. Solara Remote Data Delivery Incorporated is a Canadian company that designs, manufactures and markets handheld satellite communication devices. Solara is developing an add-on module, which would enable them to adapt their handheld device to a users smartphone. Solara has a need to develop an antenna system that will reduce field exposure levels when the handheld is placed near the user, while still achieving an acceptable signal. Solara is partnering with Dr. Greg Bridges in the Advanced RF Systems Lab at the University of Manitoba to develop an adaptive system that will detect the presence of a user by monitoring the impedance change of the transmit antenna and then guide the radiation emanated by the antenna away from the user's body in order to reduce field exposure level. The adaptive antenna system would solve one of the major challenges for Solara to bring this new type of product to market. A handheld smartphone add-on module that enables Iridium system access has the potential to give Solara's satellite cellphone technology a competitive edge. It would provide users in remote locations a reliable means of communications, and is of importance in Canada's northern areas.