The Uncertainties and Repeatability Limitations of Transmitter and Receiver Performance Assessments Posed by Head Phantoms

Abstract

Service providers request minimal requirements for the over-the-air performance of handheld devices to maintain high quality services for their mobile networks. Standards for assessing performance in laboratories are currently being developed in order to minimize costly and non-standardized field measurements. The US-based Cellular Telecommunications & Internet Association (CTIA) is currently the only organization that has issued a mandatory standard for over-the-air performance tests [1]. The basis of the test is measurement of the 3D radiation pattern in order to obtain the magnitude and direction of radiating energy while the phone is mounted on a head phantom in a talking position. There are five key parameters: 1) the total radiated power (TRP), 2) the peak effective isotropic radiated power (EIRP), 3) the antenna efficiency, i.e., the ratio of TRP and antenna input power, 4) the antenna gain and 5) the nearhorizontal partial radiated power (NHRP+/-30°, NHRP+/-45°). In addition, the phone must be compliant with the electromagnetic safety limits defined for compliance test procedures, e.g., [2].