amplifier for a wireless receiver , the amplifier comprising a voltage amplifier module having a voltage gain switchable between a first voltage gain value and a second voltage gain value higher than the first gain value , and a resistance module having a resistance switchable between a first resistance value and a second resistance value higher than the first resistance value , an output of the voltage amplifier module being connected to an input of the resistance module , the amplifier further comprising a set of switches configured to set the voltage gain value and the resistance value , the amplifier being operable in :— a nominal mode of operation in which the voltage gain value is set to the second voltage gain value , the resistance value being set to the second resistance value , and — a high linearity mode of operation in which the voltage gain value is set to the first voltage gain value to improve linearity of the amplifier , the resistance value being set to the first resistance value to have the same ratio of the voltage gain value to the resistance value as in the nominal mode of operation .