# Analysis and Design of a Diplexing Power Divider for Ku-Band Satellite Applications
## 1 Introduction
This technology offers compact dimensions, cost-effectiveness, high quality, and exceptional performance. To develop SIW duplexing devices (which means the separation of the functions of transmission and reception), a T-junction is often required to provide the matching and isolation requirements between the input port and two separate channel filters. This T-junction occupies a certain space in architecture [39]. Dual-mode duplexing can remove T-junction size overhead while maintaining design flexibility and performance improvement. These structures have a compact size, but suffer from a narrow operating bandwidth. Designing high-performance and compact components with integration and modularity features for radio frequency front ends is highly desirable in many communication systems [40]. The concept of modularity presents a promising avenue for seamlessly integrating cutting-edge electronics, an apt approach to the cost-effective implementation of fully tailored and adaptable electronic devices. By embracing modularity, the capacity to assemble and integrate individual modules with distinct functionalities provides a flexible framework for crafting customized and responsive electronic systems that align precisely with specific requirements. This approach not only streamlines the development process but can also significantly reduce the costs associated with intricate electronic device realization [41; 42]. A lot of interest has been attracted to the integration of multifunctional microwave components, such as multiband and filtering dividers [43; 44; 45; 46], diplexer antennas [47; 48; 49; 50], etc. In long-distance communication systems, low-profile diplexing devices are paramount. These devices play a pivotal role in efficiently guiding and separating electromagnetic signals along designated pathways. By integrating these compact and versatile diplexers into the communication infrastructure, the transmission and reception of signals across long distances are optimized. This optimization is achieved by strategically channeling distinct frequency bands through the diplexing components. This enhances the overall efficacy and reliability of the communication system. The utilization of these diplexing devices improves signal management and reduces interference and signal degradation. This ensures seamless and dependable long-distance communication. The integration of these components with power dividers could benefit from size reduction and loss reduction in antennas used, for example, in deep space telecommunications. This paper presents the analysis and design of an innovative compact Ku-band SIW duplexing power divider. The proposed concept is based on extended SMA connectors, which are used as a transition between two stacked SIW channels. This innovative approach aims to achieve improved signal integrity and efficient signal propagation in Ku- band frequency applications. The proposed transition behaves like two pairs of bandpass filters effectively separating the channels. However, the unique aspect lies in its compact size, which the occupied size is much smaller than the size of two regular bandpass filters. The developed duplexing power divider has a simple topology and shows great potential for excellent integration with other planar components. The remainder of the paper is organized as follows. An SIW diplexing circuit and its characteristics are described in Section 2. In this section, a parametric study is provided to show the effect of some important parameters on S-parameters. In Section 3, the procedure for designing a diplexing power divider is presented. Then, its experimental results are presented and discussed in this section. Finally, concluding remarks are given in Section 4.