CubeSats, a type of miniaturized satellites with the benefits of low cost and short deployment period, have attracted intensive research interest recently and have been regarded as the promising future for satellite communication. With increasing service demands, uncoordinated inter-satellite communication without any intelligent scheduling or budgeting of frequency and power can no longer satisfy the need for development. In this work we evaluate the benefit of frequency scheduling in improving transmission data rate of CubeSats, using different operating frequencies, including microwave, millimeter wave and optical frequencies. A joint frequency scheduling and power allocation scheme is designed to provide the optimal transmission rate data under transmit power and throughput constraints. Simulation results demonstrate the inter-satellite links of CubeSats with frequency scheduling and power allocation can achieve higher transmission data rate than traditional operation conditions with fixed frequency or fixed power.