This　paper　presents　a　multiband　joint　cooperative　spectrum　sensing　scheme.　For　the　local　detection　of　each　frequency　band,　two　thresholds　can　be　calculated　according　to　noise　uncertainty　and　a　secondary　user　can　decide　whether　there　are　primary　users　who　utilize　multiband　joint　detection.　For　the　uncertain　frequency　band　with　its　test　statistic　falling　into　the　two　local　detection　thresholds,　the　multi-point　cooperative　spectrum　sensing　is　performed.　In　this　scheme,　secondary　users　transfer　the　sensing　information　by　utilizing　the　idle　frequency　bands,　rather　than　only　depending　on　the　common　control　channel.　Analytical　and　simulation　results　show　that　the　new　scheme　can　decrease　the　communication　overhead　of　the　common　control　channel　and　obtain　a　smaller　miss　alarm　probability　for　the　uncertain　spectrum　bands　compared　to　traditional　cooperative　sensing　schemes.