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The Earth Station
Published in Jerry D. Gibson, The Communications Handbook, 2018
Local authorities will also be able to provide information regarding zoning restrictions that may limit the placement of Earth station facilities. In 1996, the FCC issued a report and order (FCC 96-326) adopting new guidelines for evaluating the environmental effects of radio frequency (RF) radiation from FCC licensed transmitters. As part of this report, the FCC has adopted RF exposure limits for both controlled and uncontrolled environments at Earth station facilities. An uncontrolled environment includes areas around an Earth station site where individuals might be exposed to RF radiation without their knowledge. The Earth station operator will need to include proof that a proposed antenna installation will meet RF exposure limits when submitting a license application to the FCC. In planning a new Earth station installation, a link budget is normally prepared, which determines the maximum HPA power output that will be required. The link budget also takes into account the proposed transmit antenna size, satellite transponder characteristics, and atmospheric losses and determines overall quality of service. Calculations can be performed using this data to determine the level of RF exposure that the Earth station will present to surrounding areas. In most cases, the services of a professional engineering firm should be contracted to perform the calculations.
Cellular Systems
Published in Lal Chand Godara, Handbook of Antennas in Wireless Communications, 2018
Link budget is a name given to the process of estimating the power at the receiver site for a microwave link taking into account the attenuation caused by the distance between the transmitter and the receiver. This reduction is referred to as the path loss. In free space the path loss is proportional to the second power of the distance; that is, the distance power gradient is two. In other words, by doubling the distance between the transmitter and the receiver, the received power at the receiver reduces to one fourth of the original amount.
Satellite orbital parameters and outline satellite communication principles
Published in L. Tetley, D. Calcutt, Understanding GMDSS, 2012
A satellite system must be planned in order to ensure that the transmission link can be satisfactorily established and maintained, having regard to the conditions under which the link is operated. A link will experience various gains and losses and collecting the gains and losses together produces what is known as the link budget.
Efficient microwave power transfer system using retrodirective antenna array
Published in International Journal of Electronics, 2023
Changyoung An, Heung-Gyoon Ryu
The path loss greatly reduces the power transmission efficiency and may change as the position of the power transmitter or power receiver changes. Moreover, the conversion efficiency of the RF-DC rectifier can also reduce the power transmission efficiency. In order to overcome the efficiency reduction caused by these factors, it is effective to increase the antenna gain of the power transmitter and the power receiver. To achieve the antenna gain required by the system, multiple-antenna modules should be used. However, the increase in antenna modules increases the form factor of the entire system, so the system should be designed with this in mind. After using these factors to determine the system configuration for the power transmission paths between the power transmitter and the power reception, the input power values that allow the RF-DC rectifier to achieve maximum conversion efficiency should be identified. The transmission power of the transmitter must be determined. The required transmission power can be obtained by amplifying the pilot signal, and after analysing the link budget for the pilot transmission and reception path, the amount of amplification required in the power transmitter should be determined. Based on this design method, detailed parameters for designing a system with power transmission distance of 4 m and efficiency of 5% are shown in Table 1.