Numerical simulation of sound absorption coefficient of wood perforated wall panel with uniform small geometric patterns

Wood perforated wall panel with geometric pattern is a form of direct piercing carved wood panel (DPCWP). It has been extensively used as decoration element in Malay architecture especially in palaces, mosques, public building and some houses. The important aspect focused on this DPCWP is its ability to act as sound absorber. The sound absorption coefficient (SAC) an, of wood perforated wall panel with uniform and small geometric patterns at 1kHz to 4kHz frequency band shall be improved optimally through the contribution of perforation ratio and resonance frequencies. From previous findings, the hypothesis is that wood perforated wall panel with uniform small geometric patterns gives good sound absorption performance at 1kHz to 4kHz frequency region. Two patterns of DPCWP are designed using resonance frequency technique at 1/3 octave centre frequency from 1.6kHz to 5kHz with perforation ratio in the range of 35% to 40% and have been successfully investigated. Simulation process is carried out using BEASY acoustics software, which is an established numerical modelling tool for Boundary Element Method (BEM) works. Numerical modelling based on BEM has been widely used for engineering design and prediction. Results show that it has almost the same trend with those in previous results. However, at frequency 1kHz to 4kHz, an results show an increment to the higher an compared to the previous results which are show small an values at the same frequencies. The higher an phenomena at high frequencies shown by the best samples, S5 and S7 are due to resonance frequency inside the air column in DPCWP apertures. Noise reduction coefficients (NRC) calculated in the region of 0.75 to 0.95 prove that DPCWP with uniform and small geometric pattern able to act as good sound absorber. This finding allows DPCWP to be used as sound absorber more effectively mosques and other enclosed rooms

Novel Artificial Magnetic Conductor for 5G Application

A design of novel bendable Artificial Magnetic Conductor (AMC) structures has been presented in this paper in two selected of frequencies at 5G application. These designs started with a square patch shape and continued with the combination of circular and Jerusalem shape which resonate at a frequency of 18 GHz and 28 GHz. Details of the theory and the structures of AMCs are explained. The reflection phase, bandwidth, angular stability and dispersion diagram were studied. The simulated results plotted that the novel AMC has good bandwidth and size is reduced by 53 % and 55 % for both frequencies. Other than that, it is also proved that the novel AMC has a stable reflection phase and no band gap performs at the specific frequency. The good performances of this novel AMC make it useful in order to improve antenna’s performanc

Improvement Antenna Performance by using Artificial Magnetic Conductor at 28 GHz

The configurations of single patch antenna integrated with three different designs of patch artificial magnetic conductor (AMC) are presented in this paper in order to investigate the gain, radiation pattern, directivity and bandwidth of the antenna at a frequency of 28 GHz. Three cases of design configuration between patch antenna and three different designs of AMC are analyzed. First, configuration of patch antenna integrated with three designs of patch AMC. Second configuration of patch antenna integrated with non periodic patch AMC and third multilayer patch antenna with patch AMC. The details theory of the design configuration is explained. The simulated reflection coefficient and radiation pattern is presented. The simulated results showed that the gain, directivity and impedance bandwidth of all the design techniques are increased compared to patch antenna without AMC. For the first case, design of patch antenna integrated with design 1 AMC offer 13.96 % bandwidth and 12 % of the gain compared to patch antenna without AMC. In the second case, the overall size is reduced by 9.2 % and 14.14 % , respectively, compared with design in the first case. The third case of design structures provides more gain and bandwidth more than 3.57 %. In addition, the size is reduced compared to the previous two cases. Therefore, the result indicates the capability of this antenna integrated with AMC to be used for future 5G application. Index Terms: Artificia

Dipole Antenna backed by 8-CBU AMC-EBG and 8-CBU FSS at 5.8 GHz

This paper investigates the performances of dipole antenna, incorporated with and without 8-Connected Branches Uniplanar Artificial Magnetic Conductor-Electromagnetic Band Gap (8-CBU AMC-EBG) and 8 Connected Branches Uniplanar Frequency Selective Surface (8-CBU FSS) at 5.8 GHz. The designs are simulated on Arlon AD-350 with permittivity, ɛr = 3.50, thickness, h = 1.016 mm and tangent loss, δ = 0.0026. Due to the flexibility of the material used as a substrate, the effect of different angle is investigated. Both the 8-CBU AMC-EBG and 8 the CBU FSS act as a reasonably good ground plane for the dipole antenna and help to improve the realized gain and the radiation patterns by pushing the front lobe, while at the same time reducing the side lobes. The maximum improvements led by dipole antenna with 8-CBU AMC-EBG are 8.54 dB of realized gain is achieved and approximately 6.53 dBi of the directivity of front lobe is pushed higher than the dipole alone while the side lobe is significantly lower than with 8-CBU FSS. The designs of 8-CBU AMC-EBG and 8-CBU FSS can be applied to dipole antenna application such as Wi-fi and other on-body communication devices

Improvement Antenna Performance by using Artificial Magnetic Conductor at 28 GHz

The configurations of single patch antenna integrated with three different designs of patch artificial magnetic conductor (AMC) are presented in this paper in order to investigate the gain, radiation pattern, directivity and bandwidth of the antenna at a frequency of 28 GHz. Three cases of design configuration between patch antenna and three different designs of AMC are analyzed. First, configuration of patch antenna integrated with three designs of patch AMC. Second configuration of patch antenna integrated with non periodic patch AMC and third multilayer patch antenna with patch AMC. The details theory of the design configuration is explained. The simulated reflection coefficient and radiation pattern is presented. The simulated results showed that the gain, directivity and impedance bandwidth of all the design techniques are increased compared to patch antenna without AMC. For the first case, design of patch antenna integrated with design 1 AMC offer 13.96 % bandwidth and 12 % of the gain compared to patch antenna without AMC. In the second case, the overall size is reduced by 9.2 % and 14.14 % , respectively, compared with design in the first case. The third case of design structures provides more gain and bandwidth more than 3.57 %. In addition, the size is reduced compared to the previous two cases. Therefore, the result indicates the capability of this antenna integrated with AMC to be used for future 5G application

Dipole Antenna Backed By 8-CBU AMC-EBG And 8-CBU FSS At 5.8 GHz

This paper investigates the performances of dipole antenna, incorporated with and without 8-Connected Branches Uniplanar Artificial Magnetic Conductor-Electromagnetic Band Gap (8-CBU AMC-EBG) and 8 Connected Branches Uniplanar Frequency Selective Surface (8-CBU FSS) at 5.8 GHz. The designs are simulated on Arlon AD-350 with permittivity, ɛr = 3.50, thickness, h = 1.016 mm and tangent loss, δ = 0.0026. Due to the flexibility of the material used as a substrate, the effect of different angle is investigated. Both the 8-CBU AMC-EBG and 8 the CBU FSS act as a reasonably good ground plane for the dipole antenna and help to improve the realized gain and the radiation patterns by pushing the front lobe, while at the same time reducing the side lobes. The maximum improvements led by dipole antenna with 8-CBU AMC-EBG are 8.54 dB of realized gain is achieved and approximately 6.53 dBi of the directivity of front lobe is pushed higher than the dipole alone while the side lobe is significantly lower than with 8-CBU FSS. The designs of 8-CBU AMC-EBG and 8-CBU FSS can be applied to dipole antenna application such as Wi-fi and other on-body communication devices

Proximity Coupled Antenna With Star Geometry Pattern AMC Ground Plane

In this paper, a conventional proximity coupled microstrip antenna operating at 2.45 GHz is firstly designed as a reference antenna. Then, the proximity coupled microstrip antenna is incorporated with a star geometry pattern artificial magnetic conductor (AMC) as the ground plane. Performance comparison is analyzed between the conventional antenna and the antenna with the AMC ground plane. The proximity antenna with star geometry pattern AMC ground plane successfully enhances the efficiency and gain by 8 % and 3 % as compared to the conventional antenna. In addition, the size of the proximity antenna with star geometry pattern AMC ground plane is reduced by 13 % as compared to conventional antenna. It shows that AMC as a ground plane to the antenna are able to reduce the size, enhance the gain and efficiency of the antenna