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Planning permission
Published in Ray Tricker, Samantha Alford, Building Regulations in Brief, 2022
The prior approval procedure applies to the construction, installation, alteration or replacement of: An antennae (including any supporting structure) which exceeds the height of the building or structure (other than a mast) by 4m or more at the point of where it is installed or to be installed.A public call box.A ground-based mast of up to and including 15m in height.A mast of up to and including 15m in height installed on a building or structure.Development ancillary to radio equipment housing (for example, fences or access roads).Radio equipment housing with a volume of 2.5m3.
A Hybrid Fractal Metamaterial Antenna for Wireless Applications with Gain Enhancement
Published in IETE Journal of Research, 2023
Ritesh Kumar Saraswat, Mithilesh Kumar
Figure 18(c) represents the attachment of the proposed multiband antenna with the metal sheet. The antenna is attached with the sheet by using the supporting mast of length 20 mm. The comparative antenna gain is indicated in Figure 19 for three-mode condition of antenna with FSS, with the metal sheet and without FSS and the metal sheet. It is observed that antenna gain is enhanced by using FSS and metal sheets with a structure. The gain enhancement is achieved due to the improvement in the directivity of the antenna when applying the FSS structure and the metal sheet. The gain is improved by approximately 4-5 dB when using FSS and the metal sheet. From Figure 19, it is also noticed that the antenna gain is higher at the higher frequency region than lower frequency region. The gain decreases for lower frequency (below 5 GHz) because of the poor characteristics (low gain) of the reference horn antenna which is used in the Antenna Measurement System. At higher frequencies, the aperture area is improved, that is responsible to increase the antenna gain (above 9.0 GHz).
Optimum Selection of Communication Tower Structures Based on Wind Loads & lifecycle cost analysis
Published in Cogent Engineering, 2022
Yasmin Elhakim, Tawfik Ismail, Irene Fahim
According to Gao et al. (2018), failure of monopole towers or guyed mast usually happens because of guys rupture or overall turning. However, for the case of the latticed tower, a progressive collapse analysis under design and accidental loads should be carried out, as it is more complicated to determine the causes of failure. In their study, they conducted progressive collapse analysis for latticed communication towers under wind loads with different wind directions. This analysis was conducted on two different configurations of 50 m latticed towers, namely, standard tripole tower and standard angle tower (as defined by the Chinese government standard drawing collection of a telecommunication steel tower, DCTST 2014) using ABAQUS software. According to their findings, in order to minimize the telecommunication towers and collapse probability due to wind loads, first unfavorable wind direction should be avoided through proper design. Second, critical leg member that tend to trigger collapse should be protected. Third, anti-collapse design should be done using an alternative load path or bridge-over method to protect the tower against collapse.
Performance analysis of low-cost GNSS stations for structural health monitoring of civil engineering structures
Published in Structure and Infrastructure Engineering, 2022
Nicolas Manzini, André Orcesi, Christian Thom, Marc-Antoine Brossault, Serge Botton, Miguel Ortiz, John Dumoulin
An automatic detection test has been proposed (Figure 6), to check if shifting the GNSS station is correctly detected over time. The test is based on threshold detection applied to the horizontal position derivative (speed). Derivative is averaged over a sliding window of five measurements to cancel any false-positive due to GPS noise. If the shift is detected in this time window, the detection is considered successful. Performance of the solution is then evaluated based on the ratio of successful detections. In a second experiment E2b, a similar approach was used to evaluate the detection of vertical jumps. The antenna was mounted on a tripod with a graduated mast (millimeter scale) located a few meters away from the reference station. Similar qualification protocol was applied.