— In this paper, we study the weighted sum rate maximization of multicell cellular cognitive radio networks (CRNs) which are overlaid with multicell primary radio networks (PRNs). We assume each CRN cell is collocated with a PRN cell and has a cellular structure with access point (AP) and multiple secondary users (SUs). We propose a unified framework to determine the operation parameters of the CRNs in the multicell environment. First, to avoid unacceptable interference to primary users (PUs), we propose methods to determine the power spectral masks (PSMs) of SUs and APs in uplink and downlink transmissions at each subchannel based on the target signal-to-interference-plus-noise ratio (SINR) outage probability of PRN base station (BS) receivers. Second, we utilize the duality optimization tool and design weighted sum rate maximization schemes which include the PSM optimally. Third, we accurately model the intercell interferences between CRNs and mutual interferences between the PRNs...