In-Band Full Duplex

The global wireless industry works like clockwork. Every decade, the global community ratifies a new generation of cellular standards relying on advances from the past decades; a similar rhythm drives Wi-Fi standardization. In all standards, cellular and Wi-Fi, a core design principle is that wireless nodescan either transmit or receive in a given frequency band. However, a node cannot simultaneously transmit and receive in the same frequency band due to high self-interference from its own transmitted signal that can drown out the receive signal. As a result, to enable bidirectional communications between nodes, network designs have relied on partitioning time and frequency using a mix of time-division duplex and frequency-division duplex. In short, wireless designs have not considered in-band full duplex (IBFD) as a building block.