The communications industrial standard YD/T 1885-2009 provides the types of headset interfaces, the performance requirements and test methods. Since the release of this standard, more and more manufacturers have adopt...The communications industrial standard YD/T 1885-2009 provides the types of headset interfaces, the performance requirements and test methods. Since the release of this standard, more and more manufacturers have adopted the concentric connector, which gives more choices to consumers and also has benefits on the environmental protection and the healthy development of the mobile terminal industry. Now, the universal headset interface has been included in the draft ITU-T recommendation P.381. lts internationalization will further enhance the universality of the mobile phone headset interlace. It is China's another great contribution to the international standardization following the standard of universal power adapter for mobile phones.展开更多
Based on the Marshall-Palmer,Weibull raindrop size distribution and Mie electromagnetic scattering model,the relationships of attenuation coefficient of terahertz(THz) atmospheric window waves with precipitation rate ...Based on the Marshall-Palmer,Weibull raindrop size distribution and Mie electromagnetic scattering model,the relationships of attenuation coefficient of terahertz(THz) atmospheric window waves with precipitation rate and temperature are studied.Furthermore,combined with the loss of electromagnetic wave transmission in free space,the attenuation of THz communication and the transmission of current mobile communication signals through rain are compared and analyzed.The results show that the attenuation coefficient of THz transmission is increased with increasing precipitation rate,the difference of attenuation coefficient at different THz window waves is small,and the maximum difference is about 3 dB.The rain attenuation of THz wave is first decreased and then increased with increasing temperature,but the temperature has little effect on it.The attenuation of THz wave through rain is much larger than that of mobile communication signal.展开更多
文摘The communications industrial standard YD/T 1885-2009 provides the types of headset interfaces, the performance requirements and test methods. Since the release of this standard, more and more manufacturers have adopted the concentric connector, which gives more choices to consumers and also has benefits on the environmental protection and the healthy development of the mobile terminal industry. Now, the universal headset interface has been included in the draft ITU-T recommendation P.381. lts internationalization will further enhance the universality of the mobile phone headset interlace. It is China's another great contribution to the international standardization following the standard of universal power adapter for mobile phones.
文摘Based on the Marshall-Palmer,Weibull raindrop size distribution and Mie electromagnetic scattering model,the relationships of attenuation coefficient of terahertz(THz) atmospheric window waves with precipitation rate and temperature are studied.Furthermore,combined with the loss of electromagnetic wave transmission in free space,the attenuation of THz communication and the transmission of current mobile communication signals through rain are compared and analyzed.The results show that the attenuation coefficient of THz transmission is increased with increasing precipitation rate,the difference of attenuation coefficient at different THz window waves is small,and the maximum difference is about 3 dB.The rain attenuation of THz wave is first decreased and then increased with increasing temperature,but the temperature has little effect on it.The attenuation of THz wave through rain is much larger than that of mobile communication signal.