The thermal neutron, epithermal neutron and high-energy photon fluence were measured in this work around the Varian 21EX 23 MV CLINAC, which is operated in Albairouni hospital in Damascus, Syria. Background: Photoneutron measurements around medical CLINAC aim to protect both patients and staff from unwanted radiation. Materials and methods: Neutron and photon activation techniques were applied using gold foils. Results: It was found that high-energy photons fluence has practically a constant value in the field size. The thermal and epithermal neutron fluence along ox and oy axes has the same order of magnitude. Conclusion: Gold foils have been used successfully to measure neutron flux and high-energy photons simultaneously using activation techniques.

An ultra-wide band (UWB) antenna with C-band and X-band notches for wireless communication is presented. The designed structure is printed on a material of "Rogers 4350B" with ε r = 3.66, tan δ = 0.0037, and a thickness of 0.508 mm. This structure is designed to operate at a UWB range starting from 3.3 GHz up to 10.15 GHz with a stopband range from 6.75 GHz to 8.5 GHz. The rejected bands are the upper C-band (6.75 GHz-8 GHz) and the uplink X-band of the satellite (space to earth) from 7.25 GHz to 7.75 GHz. The overall antenna size is optimized, and its dimensions are 21 × 30 × 0.508 mm 3 . The antenna gain varies from 2.1 to 4.2 dBi at the passband, and its total radiation efficiency is 96.4%. The suggested structure is designed and simulated using CSTMWS software. Moreover, a prototype of the proposed structure is fabricated and measured. The fabrication process was done using photolithography techniques, and the measurements were done using an R&S vector network analyzer. Good agreement is achieved between the simulated and measured results.

In this paper we present the design of a leaky wave antenna based on Substrate Integrated Waveguide (SIW) loaded by Complementary Split Ring resonator (CSRR). The proposed antenna is designed for 5G application with a center frequency around 28 GHz. The antenna is implemented on Roger RT/Duriod 5880. The loading CSRRs are designed to resonate at 28 GHz. The design is simulated by using both High-Frequency Simulation Software (HFSS) and Computer Simulation Technology (CST) for verification. Experimental measurements are also presented.

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A new sub-THz leaky wave antenna based on grounded silicon substrate for chip to chip communication applications is presented. The proposed leaky wave antenna is based on sinusoidally modulated surface reactance. This surface reactance is implemented by using varying width strips on the top of a grounded silicon substrate. Two approaches for developing these strips are studied. These two approaches are based on either highly doped silicon strips or gold strips. Both the doped silicon and the gold are presented by using their corresponding Drude models at the proposed operating frequency. Comparisons between the properties of these two approaches are presented to show the applicability of each one.