This paper presents a design of efficient smart jammer to jam the 4G signals, specifically band 3 and band 40 which can be predominantly used in India. The MATLAB Simulink tool was used for the analysis of the circuit design. Simulink, an advanced tool gives accurate results comparable to real time analysis. The DSP toolbox of the Simulink library has been largely used to construct and view the results of the model. The main objective of this paper is to receive the LTE signals, filter band 3 and band 40, add noise and increase the amplitude of the signal. The uniqueness of this design is the use of full wave rectifier in the circuit and the trigger enabled blocks. Full wave rectifier with added circuitry acts as a trigger to the jammer which contains the noise block and the gain block. Sine wave generators were used to replicate real time signals and additional signals were added as noise. The advantage of the design is when none of the bands are detected; the output will not be generated, thus saving power. The incorporation of the detector circuit and trigger circuit ensures that power is not wasted by the jamming circuit when there signal is not detected. These jammers can be used in examination halls, conference halls and in secure location where telecommunication signals are unwanted.