Lokman Kuzu

Three-way substrate integrated waveguide (SIW) power divider design

In this paper, an X-band 1×3 substrate integrated waveguide (SIW) power divider design is presented. The designed SIW power divider provides equal amplitude with uniform phase distribution at the each output port. It has also a satisfactory operating bandwidth and low insertion loss. Moreover, the return loss is approximately 25 dB at the design frequency as shown in the EM simulation results.

Reliability analysis of TUSAT satellite communication payload

A communication satellite consists of subsystems which are functioning together to form a whole system. All subsystems consist of thousands of components and there is no possibility of repair once the satellite launched into orbit. Therefore, the necessity of high reliability becomes a rule rather than an exception. TUSAT (Turkish National Communication Satellite) is planned to have both C and Ku band payloads operating in geostationary orbit. This paper presents the reliability analysis of its payload as support to the overall satellite level system design. The paper includes payload redundancy schemes and reliability budgets based on the main subsystem assumptions.

Implementation of three-way power divider based on substrate integrated waveguide

This paper presents the design, fabrication, and measurement results of an X-band 1×3 substrate integrated waveguide (SIW) power divider. The 1×3 SIW power divider provides equal amplitude with uniform phase distribution at each output port. These features are demonstrated by measurements experimentally. The amounts of measured power at the output ports are quite close to ideal power equality factor (4.77 dB) for three-way power division. Operating bandwidth of the fabricated divider is nearly 17.5% and reflection coefficient is better than −18.75 dB at the design frequency of 10 GHz as shown in both simulation and measurement results.

Complex permittivity measurements of dielectrics for space antenna radome and substrates in X-band

A variety of material measurement systems based on transmission/reflection line method are available to characterize the dielectric properties of materials by extracting the S-parameters using a Vector Network Analyzer (VNA). A waveguide material measurement facility based on transmission/reflection line method has been developed in-house in order to accurately deduct relative dielectric permittivity and tangent loss values of dielectric materials used for manufacturing antenna radome and substrate. In this paper, the experimental measurements of VESPEL, PTFE (Teflon), and RO5880 have been realized in X-band (8–12 GHz) with a very low standard deviation.

A planar Ku band antenna for satellite communications

In this study a planar Ku band antenna is designed and built for satellite communications especially to receive TV signals in Turkey. This paper summarizes the design and manufacturing phases of the study and demonstrates the simulation results of the prototype antenna.

Ku band planar array antenna for satellite TV signal reception

A planar Ku band antenna is designed and built for satellite communications especially for TV reception in Turkey. The design, manufacturing and test phases of the study are summarized in this paper.

Preliminary design of TUSAT satellite communication payload

TUSAT (Turkish National Communication Satellite) is a conceptual satellite design which is the first step of the Turkish Space Program aimed at gaining the capability of designing and manufacturing Geostationary Earth Orbit Communications Satellites. TUSAT is planned to be located at an orbital longitude of 42o East, to provide C and Ku-band communication services. This work presents the preliminary payload design which includes mission objectives, frequency plan, service areas, repeater block diagrams and budgets.