Commonly, the function XOR is used on a bit-level. Usually, the function XOR is used to link two consecutive values. The next value of the sequence depends on the current value. Also the simulation problem for long bit LFSR on FPGA is presented. A linear-feedback shift register is a shift register which will produce a sequence of numbers. The comparative study of 8, 16 and 32 bit LFSR on FPGA is shown here to understand the on chip verification. The analysis is conceded out to find number of gates, memory and speed requirement in FPGA as the number of bits is increased. Here in this paper we implemented 8, 16 and 32-bit LFSR on FPGA by using VHDL to study the performance and analysis the behavior of randomness. As it is simple counter so it can count maximum of 2n-1 by using maximum feedback polynomial. The total number of random state generated on LFSR depends on the feedback polynomial. As FPGAs is used to implement any logical function for faster prototype development, it is necessary to implement the existing design of LFSR on FPGA to test and verify the simulated & synthesis result between different lengths. It is more important to test and verify by implementing on any hardware for getting better efficient result. LFSR based PN Sequence Generator technique is used for various cryptography applications and for designing encoder, decoder in different communication channel.
