A method of operating a node of a radio access network which communicates over a radio interface with a wireless terminal, the method comprising: the node obtaining with respect to the wireless terminal both a terminal speed value and a throughput value; the node using both the terminal speed value and the throughput value to make a determination when to switch between plural transmission modes, at least one of the transmission modes comprising a multiple input multiple output, MIMO, mode; and the node using both the terminal speed value and the throughput value to make a determination when to switch between plural MIMO modes for communicating in downlink transmission with the wireless terminal, the plural MIMO modes comprising a first mode wherein open loop MIMO operates with cyclical diversity delay and a second mode wherein open loop MIMO operates without cyclical diversity delay, wherein the node determines in which of the plural modes the node is to operate with respect to the wireless terminal by performing the following acts: if the node is in the first mode and the terminal speed value exceeds a terminal speed threshold, keeping the downlink transmission in the first mode; if the node is in the first mode and the terminal speed value does not exceed the terminal speed threshold: switching the downlink transmission to the second mode when a first mode throughput value exceeds a throughput threshold; and keeping the downlink transmission in the first mode when the first mode throughput value does not exceed the throughput threshold; if the node is in the second mode and the terminal speed value exceeds the terminal speed threshold, switching the downlink transmission to the first mode; and if the node is in the second mode and the terminal speed value does not exceed the terminal speed threshold: switching the downlink transmission to the first mode when a second mode throughput value does not exceed the throughput threshold; and keeping the downlink transmission in the second mode when the second mode throughput value does exceed the throughput threshold. the node obtaining with respect to the wireless terminal both a terminal speed value and a throughput value; the node using both the terminal speed value and the throughput value to make a determination when to switch between plural transmission modes, at least one of the transmission modes comprising a multiple input multiple output, MIMO, mode; and the node using both the terminal speed value and the throughput value to make a determination when to switch between plural MIMO modes for communicating in downlink transmission with the wireless terminal, the plural MIMO modes comprising a first mode wherein open loop MIMO operates with cyclical diversity delay and a second mode wherein open loop MIMO operates without cyclical diversity delay, wherein the node determines in which of the plural modes the node is to operate with respect to the wireless terminal by performing the following acts: if the node is in the first mode and the terminal speed value exceeds a terminal speed threshold, keeping the downlink transmission in the first mode; if the node is in the first mode and the terminal speed value does not exceed the terminal speed threshold: switching the downlink transmission to the second mode when a first mode throughput value exceeds a throughput threshold; and keeping the downlink transmission in the first mode when the first mode throughput value does not exceed the throughput threshold; if the node is in the second mode and the terminal speed value exceeds the terminal speed threshold, switching the downlink transmission to the first mode; and if the node is in the second mode and the terminal speed value does not exceed the terminal speed threshold: switching the downlink transmission to the first mode when a second mode throughput value does not exceed the throughput threshold; and keeping the downlink transmission in the second mode when the second mode throughput value does exceed the throughput threshold. if the node is in the first mode and the terminal speed value exceeds a terminal speed threshold, keeping the downlink transmission in the first mode; if the node is in the first mode and the terminal speed value does not exceed the terminal speed threshold: switching the downlink transmission to the second mode when a first mode throughput value exceeds a throughput threshold; and keeping the downlink transmission in the first mode when the first mode throughput value does not exceed the throughput threshold; switching the downlink transmission to the second mode when a first mode throughput value exceeds a throughput threshold; and keeping the downlink transmission in the first mode when the first mode throughput value does not exceed the throughput threshold; if the node is in the second mode and the terminal speed value exceeds the terminal speed threshold, switching the downlink transmission to the first mode; and if the node is in the second mode and the terminal speed value does not exceed the terminal speed threshold: switching the downlink transmission to the first mode when a second mode throughput value does not exceed the throughput threshold; and keeping the downlink transmission in the second mode when the second mode throughput value does exceed the throughput threshold. switching the downlink transmission to the first mode when a second mode throughput value does not exceed the throughput threshold; and keeping the downlink transmission in the second mode when the second mode throughput value does exceed the throughput threshold.