Starting with a Kondo lattice model type Hamiltonian, we have studied the e_ects of impurity concen-rntration x, electric _eld, magnetic _eld, and magnetic anisotropy energy on the magnetic properties ofrnFe=GaSb diluted magnetic semiconductor. Analytical technique is employed to analyze the magnonrndispersion relation, magnetization, critical temperature Tc, speci_c heat capacity, and susceptibility ofrnthe system. Our analysis indicate the enhancement of Tc with increasing impurity concentration xrnand/or with the magnetic and electric _elds. Due to the inclusion of the magnetic anisotropic energy,rnwe could identify a signi_cant reduction of magnon dispersion/band gap energy and a slight reductionrnof magnetization. It is also shown that electric _eld and magnetic _eld have the tendency of enhancingrnthe magnetic susceptibility and lowering the magnon speci_c heat when applied separately or simultane-rnously. On the other hand, the magnon speci_c heat tends to slightly increase contrary to the magneticrnsusceptibility with increase in magnetic anisotropic energy. We have also investigated the structural andrnelectronic properties of both pristine and Fe alloyed GaSb semiconductor using generalized gradient ap-rnproximation method (GGA) for versatile pseudopotentials within the density functional theory (DFT)rnusing Quantum ESPRESSO package. These _rst-principles studies compare the lattice parameters, thernband structures, the density of states, and the corresponding projected states of Fe/GaSb and GaSb.rnOur _ndings are in good agreement with experimental results showing 1:5 to 2% lattice parameter andrn10% band gap variations and also within 3% band gap error from previous DFT calculations for GaSb.rnMoreover, the Hubbard model (DFT+U) calculations are performed for the energy band gap correctionrnfor the doped system.