  We present results on light weakly interacting massive particle (WIMP)
searches with annual modulation (AM) analysis on data from a 1-kg mass $p$-type
point-contact germanium detector of the CDEX-1B experiment at the China Jinping
Underground Laboratory. Datasets with a total live time of 3.2 yr within a 4.2
yr span are analyzed with analysis threshold of 250 eVee. Limits on
WIMP-nucleus (${\chi}$-$N$) spin-independent cross sections as function of WIMP
mass ($m_{\chi}$) at 90\% confidence level (C.L.) are derived using the dark
matter halo model. Within the context of the standard halo model, the 90\% C.L.
allowed regions implied by the DAMA/LIBRA and CoGeNT AM-based analysis are
excluded at $>$99.99\% and 98\% C.L., respectively. These results correspond to
the best sensitivity at $m_{\chi}$$<$6$~{\rm GeV}/c^2$ among WIMP AM
measurements to date.
