Frequency translating bi-directional amplifier

A frequency translating bi-directional amplifier for extending radio coverage for a first set of digital mobile radio communication devices from a plurality of digital mobile radio communication devices, the first set of digital mobile radio communication devices operating on a first frequency of a plurality of frequencies, the first frequency of the plurality of frequencies being allocated to the first set of the plurality of digital mobile radio communication devices by a trunked network using a digital modulation scheme, comprising:

• a field programmable gate array (FPGA) with local controller (CPU) and firmware configured to analyse signals of a downlink control channel of a donor base station transmitted using the first frequency allocated to the first set of digital mobile radio communication devices in order to identify control channel messages of the downlink control channel from the signals that relate to traffic channel information, and modify the control channel messages of the downlink control channel that relate to traffic channel information;
• and
• an antenna to transmit the modified control channel messages to the digital mobile radio communication devices in order to change an operating frequency of the first set of digital mobile radio communication devices from the first frequency to use a second frequency from a predetermined set of frequencies that are repeatable by the bi-directional amplifier,
• wherein the second frequency operating between the first set of digital mobile radio communication devices and the bi-directional amplifier is different from the first frequency that is used for transmitting the signals from the donor base station to the bi-directional amplifier of the trunked network.