This paper presents an experiment-based characterization of passive suppression and active self-interference cancellation mechanisms in full-duplex wireless communication systems. The study focuses on the impact of different self-interference cancellation techniques on the performance of full-duplex systems. The authors consider both passive suppression due to antenna separation and active cancellation in analog and/or digital domains. They show that the average amount of cancellation increases with the self-interference power, and that digital cancellation is more effective when applied selectively based on measured suppression values. The study also characterizes the probability distribution of the self-interference channel before and after cancellation. The results show that the rate of a full-duplex link increases as the self-interference power increases, which is counter-intuitive but follows from the increased cancellation. The authors also demonstrate that applying digital cancellation after analog cancellation can sometimes increase self-interference, and that digital cancellation is an effective "safety net" when analog cancellation is insufficient. The study also characterizes the K-factor of the self-interference channel before and after active cancellation, showing that active cancellation reduces the K-factor. The results show that the achievable rate of full-duplex systems can be higher than half-duplex systems, and that increasing the transmission power can lead to higher achievable rates. The study also presents a design rule for full-duplex systems that suggests increasing the transmission power at both nodes by the same amount can lead to higher achievable rates in both directions of the link.This paper presents an experiment-based characterization of passive suppression and active self-interference cancellation mechanisms in full-duplex wireless communication systems. The study focuses on the impact of different self-interference cancellation techniques on the performance of full-duplex systems. The authors consider both passive suppression due to antenna separation and active cancellation in analog and/or digital domains. They show that the average amount of cancellation increases with the self-interference power, and that digital cancellation is more effective when applied selectively based on measured suppression values. The study also characterizes the probability distribution of the self-interference channel before and after cancellation. The results show that the rate of a full-duplex link increases as the self-interference power increases, which is counter-intuitive but follows from the increased cancellation. The authors also demonstrate that applying digital cancellation after analog cancellation can sometimes increase self-interference, and that digital cancellation is an effective "safety net" when analog cancellation is insufficient. The study also characterizes the K-factor of the self-interference channel before and after active cancellation, showing that active cancellation reduces the K-factor. The results show that the achievable rate of full-duplex systems can be higher than half-duplex systems, and that increasing the transmission power can lead to higher achievable rates. The study also presents a design rule for full-duplex systems that suggests increasing the transmission power at both nodes by the same amount can lead to higher achievable rates in both directions of the link.