Method, apparatus, computer program product and computer readable medium are disclosed for medium access control in a wireless sensor network, wherein the wireless sensor network comprises a source node configured to send sensor information, a relay node configured to relay the sensor information and a sink node configured to receive the sensor information; said method comprising. The method comprises: scheduling wireless resource for the source node and the relay node so that the relay node can receive and relay the sensor information sent by the source node; and combining a plurality of transmissions containing the sensor information from the source node and/or the relay node in decoding the sensor information.