Embodiments of an access point (AP), station (STA) and method of communication are generally described herein. An AP may be configurable to operate as a master AP of a multi-AP group comprising the master AP and one or more satellite APs. The master AP may select, from the multi-AP group, a set of APs that is to communicate with a STA in accordance with joint processing. The master AP may allocate one or more spatial streams to each of the APs of the set of APs for a joint transmission of a null data packet (NDP) to the STA for channel sounding. The master AP may transmit an NDP announcement (NDPA) that indicates that the APs of the set of APs are to perform the joint transmission of the NDP.