In 1xEV-Do system, the access terminal (AT) measures the channel condition and reports it through the reverse-link data rate control (DRC) channel to accommodate the asymmetric high-speed forward-link data traffic. Although a high DRC rate can provide a better forward-link channel estimation that will result in a more accurate channel assignment, the generated noise rise on the reverse link will degrade the reverse-link capacity. To understand the impacts on forward-link and reverse-link capacity, link-level simulations were performed to determine the required Eb/No for a given slot-error-rate criterion in the DRC channel. The tradeoff between the erasure rate and the required Eb/No in the DRC channel was also determined based on a simple DRC threshold setting mechanism. For different DRC lengths, the impact on the forward-link and the reverse-link throughputs is discussed.