Radio Communication Repeater

My client have a radio comunication with hopping frequency working in 800 MHz Range, that only work in 50 meter radius and need to expand to 500 meter. what need to design is a repater that can receive hopping frequency and re-transmit with higher Tx power to the original receiver. it can be made into 2 repeater device A. a Transmitter that receive original hopping frequency and re-transmit to different freq (hopping is better) B. a Receiver that receive the different freq transmitted by unit A, and retransmit into original hopping frequency to the original transmitter if possible to make into single unit will be better