In this paper, we proposed a new dynamic channel allocation algorithm for TD-SCDMA with cross time slots. In order to reduce the interference in cross time slot, the mobile stations (MSs) are divided into two groups: the Near Group consisting of MSs near by the base station(BS) and the Far Group including the MSs far from the BS. The reverse link for MSs in the Near Group and forward link for MSs in the Far Group are allocated to the cross time slot. In cellular systems, a BS has multiple neighbor BSs. Some of neighbor BSs can operate in the same direction link while the others have cross time slot. Thus, it is required to determine which BS has the most significant impact in terms of interference. We divide each cell into 6 areas based on the direction of arrival of smart antenna and the most significant neighbor sector is determined with this division. The proposed allocation method and area division method can avoid the severe interference in cross time slots and increase the system capacity about 2%~9% compared to FCA, and 0.5%~1.3% compared to RCA.