Propagation delay difference reporting for multiple component carriers

A mobile terminal, comprising:

• processing circuitry, which, in operation:
• determines a reception time difference or propagation delay difference for downlink transmissions from an aggregation access point to the mobile terminal via a downlink component carrier of a first radio cell and via a downlink component carrier of a second radio cell, respectively;
• and
• aligns uplink transmissions from the mobile terminal to the aggregation access point via an uplink component carrier of the first radio cell and an uplink component carrier of the second radio cell to arrive at the aggregation access point simultaneously, the aligning including adjusting a timing advance for uplink transmissions on the uplink component carrier of the second radio cell based on a timing advance for uplink transmissions on the uplink component carrier of the first radio cell and the determined reception time difference;
• and
• a transmitter, which, in operation:
• transmits an uplink transmission to the aggregation access point via the time aligned uplink component carrier of the first radio cell and the time aligned uplink component carrier of the second radio cell;
• and
• transmits a notification to the aggregation access point when at least one of the reception time difference and propagation delay difference exceed a threshold in connection with a receiving window buffer size supported by the mobile terminal.