Narrow-Band Internet of Things (NB-IoT) offers low power and wide coverage for IoT services which reuse existing Long Term Evolution (LTE) technology. Coverage enhancement at weak signal area may be achieved by channel repetition to improve signal quality. In this paper, the performance of NB-IoT is evaluated for three different modes of deployments by repeating the downlink physical channel. It is proved that the increase in the number of repetitions will give better performance of NB-IoT system. It also shows that the standalone and guard band modes perform better compared to in-band mode.