A mobile terminal arranged to transmit uplink data to a network over a radio interface using a plurality of sub-carriers, the network being arranged to receive uplink data transmitted from mobile terminals of a first type and mobile terminals of a second type, the mobile terminal being a mobile terminal of the second type, the mobile terminals of the first type being arranged to transmit uplink data on a first group of sub-carriers of the plurality of sub-carriers over a first bandwidth and the mobile terminal is arranged to transmit uplink data on a second group of sub-carriers of the plurality of sub-carriers within the first group of sub-carriers over a second bandwidth, the second bandwidth being smaller than the first bandwidth, the mobile terminals of the first type being arranged to receive downlink data from the network over a third group of sub-carriers over a third bandwidth and the mobile terminals of the second type are arranged to receive downlink data on a fourth group of sub-carriers over a fourth bandwidth, the fourth bandwidth being smaller than the third bandwidth and the fourth group of sub-carriers being within the third group of sub-carriers, and the mobile terminal is arranged: to receive system information transmitted by a base station of the network using sub-carriers within the fourth group of sub-carriers, the system information comprising an indication of a location of a random access channel allocated on sub-carriers within the second group of sub-carriers for the transmission of random access request messages by mobile terminals of the second type and not for the transmission of random access request messages by mobile terminals of the first type, and to transmit a random access request message to the base station requesting uplink radio resources on the random access channel, wherein the mobile terminal transmits random access request messages on the random access channel. the mobile terminal is arranged: to receive system information transmitted by a base station of the network using sub-carriers within the fourth group of sub-carriers, the system information comprising an indication of a location of a random access channel allocated on sub-carriers within the second group of sub-carriers for the transmission of random access request messages by mobile terminals of the second type and not for the transmission of random access request messages by mobile terminals of the first type, and to transmit a random access request message to the base station requesting uplink radio resources on the random access channel, wherein to receive system information transmitted by a base station of the network using sub-carriers within the fourth group of sub-carriers, the system information comprising an indication of a location of a random access channel allocated on sub-carriers within the second group of sub-carriers for the transmission of random access request messages by mobile terminals of the second type and not for the transmission of random access request messages by mobile terminals of the first type, and to transmit a random access request message to the base station requesting uplink radio resources on the random access channel, wherein the mobile terminal transmits random access request messages on the random access channel.