A data transmission apparatus, comprising: a time unit determining module, configured to determine configuration information of a first time unit in a radio time window, wherein the first time unit comprises multiple sub-time units, a switching time period and a transmission time period are reserved in a first sub-time unit at an interval of at least N sub-time units in the first time unit, the switching time period is used to perform analog beam switching for a common channel and/or a common reference signal, and N is a natural number; and a data transmission module, configured to transmit the common channel and/or the common reference signal in the first sub-time unit in the first time unit according to the configuration information of the first time unit, wherein the common channel and/or the common reference signal are/is transmitted in the transmission time period; wherein the time unit determining module is further configured to determine configuration information of a second time unit in the radio time window, wherein the second time unit comprises multiple sub-time units, a switching time period and a transmission time period are reserved in the last sub-time unit in the second time unit, and the switching time period in the second time unit is used to perform analog beam switching for a traffic channel; and the data transmission module is further configured to transmit the traffic channel in the second time unit according to the configuration information of the second time unit, wherein the traffic channel is transmitted in a sub-time unit other than the last sub-time unit in the second time unit and in the transmission time period in the last sub-time unit; wherein a time period length of the transmission time period in the last sub-time unit in the second time unit is less than a length of a time period that is used to transmit the traffic channel and that is in the sub-time unit other than the last sub-time unit in the second time unit. a time unit determining module, configured to determine configuration information of a first time unit in a radio time window, wherein the first time unit comprises multiple sub-time units, a switching time period and a transmission time period are reserved in a first sub-time unit at an interval of at least N sub-time units in the first time unit, the switching time period is used to perform analog beam switching for a common channel and/or a common reference signal, and N is a natural number; and a data transmission module, configured to transmit the common channel and/or the common reference signal in the first sub-time unit in the first time unit according to the configuration information of the first time unit, wherein the common channel and/or the common reference signal are/is transmitted in the transmission time period; wherein the time unit determining module is further configured to determine configuration information of a second time unit in the radio time window, wherein the second time unit comprises multiple sub-time units, a switching time period and a transmission time period are reserved in the last sub-time unit in the second time unit, and the switching time period in the second time unit is used to perform analog beam switching for a traffic channel; and the data transmission module is further configured to transmit the traffic channel in the second time unit according to the configuration information of the second time unit, wherein the traffic channel is transmitted in a sub-time unit other than the last sub-time unit in the second time unit and in the transmission time period in the last sub-time unit; wherein a time period length of the transmission time period in the last sub-time unit in the second time unit is less than a length of a time period that is used to transmit the traffic channel and that is in the sub-time unit other than the last sub-time unit in the second time unit.