Asymptotic Hyperstability and Input–Output Energy Positivity of a Single-Input Single-Output System Which Incorporates a Memoryless Non-Linear Device in the Feed-Forward Loop

This paper visualizes the role of hyperstable controllers in the closed-loop asymptotic stability of a single-input single-output system subject to any nonlinear and eventually time-varying controller within the hyperstable class. The feed-forward controlled loop (or controlled plant) contains a strongly strictly positive real transfer function in parallel with a non-linear and memory-free device. The properties of positivity and boundedness of the input–output energy are examined based on the “ad hoc” use of the Rayleigh energy theorem on the truncated relevant signals for finite time intervals. The cases of minimal and non-minimal state-space realizations of the linear part are characterized from a global asymptotic stability (asymptotic hyperstability) point of view. Some related extended results are obtained for the case when the linear part is both positive real and externally positive and for the case of incorporation of other linear components which are stable but not necessarily positive real.This research was funded by the Spanish Government and the European Commission, grant number RTI2018-094336-B-I00 (MCIU/AEI/FEDER, UE) and by the Basque Government, grant number IT1207-19. The APC was funded by grant RTI2018-094336-B-I00 (MCIU/AEI/FEDER, UE)

DESIGN OF LOW POWER MOBILE TRANSMITTER

The objective of this project is to design a power amplifier for a new two way mobile radio product being launched by Motorola. Two-way mobile radio consists of a transmitter, receiver and a voltage-controlled oscillator. Mobile radios usually have transmitter whose power output ranges from 1 W to 50 W. Design of transmitter lineup for mobile radio involves the design of appropriate matching network for driver and power amplifier. The power and voltage control of these devices are equally important. Designing a mobile radio transmitter is regarded tricky due to difficulty in getting a robust transmitter that is stable with minimum oscillation. In this work, the design is attempted usmg Advanced Design Simulator (ADS). The design simulation provides accurate simulation on harmonic filter and antenna switch. 50 ohm matching networks have also been designed and simulated using ADS and it gives close approximation to the specifications. The radio has since been prototyped and tested. The evaluation and testing of the radio has been carried out and it satisfies the specifications that are set by the Telecommunication Industry Association (TIA). Some minor optimization has also been performed to improve the radio performance. Eventual product is a transmitter line up that function well today. 11

DESIGN OF LOW POWER MOBILE TRANSMITTER

The objective of this project is to design a power amplifier for a new two way mobile radio product being launched by Motorola. Two-way mobile radio consists of a transmitter, receiver and a voltage-controlled oscillator. Mobile radios usually have transmitter whose power output ranges from 1 W to 50 W. Design of transmitter lineup for mobile radio involves the design of appropriate matching network for driver and power amplifier. The power and voltage control of these devices are equally important. Designing a mobile radio transmitter is regarded tricky due to difficulty in getting a robust transmitter that is stable with minimum oscillation. In this work, the design is attempted usmg Advanced Design Simulator (ADS). The design simulation provides accurate simulation on harmonic filter and antenna switch. 50 ohm matching networks have also been designed and simulated using ADS and it gives close approximation to the specifications. The radio has since been prototyped and tested. The evaluation and testing of the radio has been carried out and it satisfies the specifications that are set by the Telecommunication Industry Association (TIA). Some minor optimization has also been performed to improve the radio performance. Eventual product is a transmitter line up that function well today. 11