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This paper presents an efficient digital compensator that can be used for adjustment of gain and phase imbalances in linear amplification with nonlinear components (LINC) transmitters. The proposed compensator is designed in signal component separator (SCS) block using computational digital signal processing (DSP). Complex baseband equivalent signals and systems are considered to analyze error vector magnitude (EVM) and adjacent channel power ratio (ACPR) of the transmitter. Look up tables (LUT) based on the analyzed EVM and ACPR are used to compensate gain/phase imbalances of RF paths in the LINC transmitter. The suggested method is efficient to implement using computational software and DSP, and thus the compensator is reconfigurable for various input signals and RF transmitters. The LINC transmitter with the proposed compensator is implemented, and the suggested scheme is verified by showing the improvement of EVM and ACPR performance for the transmitted signals.

This paper presents the design of a remote laboratory platform using web-based technologies for radio frequency (RF), microwave measurements and their analysis. The developed RF remote laboratory system is easy to operate using web-based graphical user interfaces in controlling the test equipments and displaying the test results. The various measurement and analysis engines for RF devices, circuits, and systems are developed using graphical language, LabView. The remote RF laboratory system with the developed user interfaces and engines is used in education and research on RF engineering. The developed system can increase efficiency of education and research on RF engineering cost-effectively by providing similar environment with an actual laboratory using web-based technologies.

In nested mobile networks, the undesirable effects due to nonoptimal routing tends to get aggravated, leading to excessively long packet sizes and transfer delays. In this paper, in order to resolve the non-optimal routing problem, also known as ‘pinball routing problem’ in the literature, we propose a new route optimization scheme where the care-of address (CoA) in each binding update (BU) message is recursively substituted by the intermediate mobile routers in the mobile network. Through qualitative and numerical analyses, we show that the proposed scheme indeed demonstrates a greatly reduced signaling overhead in terms of packet sizes and number of BU messages required, thereby reducing the RO setup time and end-to-end transfer delay. We also show that the proposed scheme can be a good solution for the so-called intra-MoNET routing problem.