Wireless Sensor Networks (WSNs) have a wide range of applications from wildlife monitoring to critical infrastructure monitoring, from traffic management to individual health management. The three primary functions of a sensor are to sense, process and communicate. After being deployed randomly over a limited area, sensors start to sense a phenomenon on a regular basis. Then, they process the raw data, and wirelessly forward it to a base station, connected to the external world, via multihop paths. The authors investigate the condition on transmission radius needed to achieve connectivity in Duty-Cycled Wireless Sensor Networks (DC-WSN).