  With the current measurements performed by CMS and ATLAS experiments, the
light charged Higgs scenario ($m_{H^{\pm}}$ $<$ 160 GeV), is excluded for most
of the parameter space in the context of MSSM. However, there is still
possibility to look for heavy charged Higgs boson particularly in the
$s$-channel single top production process where the charged Higgs may appear as
a heavy resonance state and decay to $t\bar{b}$. The production process under
consideration in this paper is $pp \ra H^{\pm} \ra t\bar{b}~+~h.c.$, where the
top quark decays to $W^{+}b$ and $W^{+}$ boson subsequently decays to two light
jets. It is shown that despite the presence of large QCD and electroweak
background events, the charged Higgs signal can be extracted and observed at a
large area of MSSM parameter space ($m_{H^{\pm}}$,tan$\beta$) at LHC. The
observability of charged Higgs is potentially demonstrated with 5$\sigma$
contours and $95\%$ confidence level exclusion curves at different integrated
LHC luminosities assuming a nominal center of mass energy of $\sqrt{s}$ = 14
TeV.
