Paving the way for future 5G technologies requires a need to overcome the spectrum crunch, which is one of the major challenges impeding the growth of wireless technology. The issue at hand becomes more pronounced when we consider IoT, where billions of devices require connectivity. This article motivates the need for exploring new spectrum opportunities with reference to the requirements of IoT networks. Millimeter wave (mmWave) spectrum is considered as a panacea for overcoming the spectrum crunch, providing the much needed breathing space for introducing new applications that require higher rates. A network based on CDSA could further improve performance by utilizing mmWave-based DBSs. The CBS operates on the sub-6 GHz single band, while the DBS possesses a dual-band capability. This article presents a new dimension to spectrum heterogeneity by utilizing a dual-band approach at the DBS. One of the unique aspects of this work includes the analysis of a joint radio resource allocation algorithm based on LDD and we compare the proposed algorithm with the maxRx, DSA and JPRA algorithms. The analysis is further expanded by showing an interplay between the utilization of licensed and unlicensed mmWave resources and how dynamic spectrum management could help in their efficient utilization.