Abstract The dynamics of bilaterally coupled Gunn oscillator driven by external periodic signal has been examined through numerical simulation and experimental observation. The coupling factors between the two oscillators in either path as well as the strength and frequency of the external periodic driving signals are key parameters to control the dynamics of Driven Bilaterally Coupled Gunn Oscillator (DBCGO) system. The numerical study explores the possibility of generation of controllable chaotic signals in DBCGO system. The present work also considers this method through a hardware experiment. For different set of coupling factors, driving signal strength and frequencies, chaotic oscillations are observed. Therefore, the DBCGO system with suitable couplings and driving signal conditions can be considered as a potential source of chaotic signals in microwave frequency range. *Author for correspondence Indian Journal of Science and Technology, Vol 7(7), 916–923, July 2014 ISSN (Print) : 0974-6846 ISSN (Online) : 0974-5645 Studies on Dynamics of Driven Bilaterally Coupled Gunn Oscillator J. Chakravorty 1 , S. Sarkar 2 and B. C. Sarkar 1* 1 Department of Physics, The University of Burdwan, Golapbag, Burdwan-713104, West Bengal, India; bcsarkar_phy@yahoo.co.in 2 Department of Electronics, Burdwan Raj College, Burdwan-713104, West Bengal, India 1. Introduction Recently, coupled oscillator systems have drawn attention of the researchers of diferent ields like theoretical physics, engineering science, biological science, chemical science and even economics and social sciences 1,2 . Diferent mod- els of such coupled oscillators have been suggested by the researchers to study the dynamics of such systems 3,4 . In the area of electronics and communication technol- ogy, coupled oscillator systems ind applications in stable signal generation, power combining, synchronous ampli- ications and so on 5,6 . At microwave frequency range, coupled oscillator systems are considered for power com- bining, spatial beam forming and phase shiting 7,8 . Chaos in such coupled oscillator array has also been discussed 9 . Recently, the dynamics and chaos in Bilaterally Coupled Gunn Oscillators (BCGO) has been reported 10 . It has been shown that, depending on free running frequen- cies of each oscillator and Coupling Factors (CF) between them, chaotic oscillations can be obtained. In this paper, the dynamics of a BCGO system, sub- jected to an external periodic driving signal has been studied. he BCGO has been set to operate in the syn- chronized mode of oscillations and an external signal is applied to one of the oscillators to examine the efect of forcing. he frequency of the external driving signal is varied keeping its power ixed at value and output spec- tra of the system are observed. he aim of the paper is to address the following problems: (i) To ind the efect of the external driving signal on the Synchronization Band (SB) of the BCGO system. (ii) To explore through numerical study the possibil- ity of generation of controllable chaotic signals in microwave (MW) frequency range using a driven BCGO system. (iii) To experimentally study the dynamics of driven BCGO system in the MW frequency domain. he paper has been organized in the following way. Section 2 describes the Driven BCGO (DBCGO) and Keywords: Coupled System, Driven Oscillator, Gunn Diode, Microwave Chao