I'm testing the Digi XBee3 Zigbee Mesh Kit with XCTU. Once configured the XBee3 the way it was mentioned in the Mesh Kit User Guide, I could only discover radio nodes with the antenna attached. And if without the antenna attached, XCTU always gives no device detected. We do not expect the design of our product to have an external antenna and we have seen devices with Xbee running without antennas attached. Is this hardware/firmware issue with the MeshKit or the Grove board?