A wireless communications device comprising: a communication subsystem comprising a variable-gain power amplifier and a signal processor coupled to the variable-gain power amplifier, the communication subsystem being configured for communication with a wireless network (219, 221) whereby a wireless signal is received at the variable-gain power amplifier from the wireless network, the variable-gain power amplifier comprising a gain input (A, B) and being configured to vary the amplification of the received wireless signal by adjusting a gain of the variable-gain power amplifier based on the voltage applied to the gain input (A, B); and a programmable battery comprising: an array of battery cells; a power output bus; a switch matrix coupled to the battery cells and the output bus, the switch matrix being configured to dynamically vary a power characteristic of power applied to the power output bus from the array of battery cells based on a power configuration command received at the programmable battery, wherein the power output bus of the programmable battery is coupled to power inputs, i.e. gain inputs and power supply inputs, of various subsystems and other electronic devices of the wireless communications device; and wherein conductors of the power output bus are each coupled to the power input of a respective subsystem or electronic device of the wireless communications device, whereby the programmable battery is configured to adjust the power supplied to the gain inputs and the power supply inputs of the subsystems/devices independently of each other; wherein the power output bus is coupled to the gain input (A, B) of the variable-gain power amplifier, and the programmable battery is configured to dynamically adjust the magnitude of the voltage applied to the gain input (A, B) of the variable-gain power amplifier in accordance with a power requirement of the wireless network (219, 221). a communication subsystem comprising a variable-gain power amplifier and a signal processor coupled to the variable-gain power amplifier, the communication subsystem being configured for communication with a wireless network (219, 221) whereby a wireless signal is received at the variable-gain power amplifier from the wireless network, the variable-gain power amplifier comprising a gain input (A, B) and being configured to vary the amplification of the received wireless signal by adjusting a gain of the variable-gain power amplifier based on the voltage applied to the gain input (A, B); and a programmable battery comprising: an array of battery cells; a power output bus; a switch matrix coupled to the battery cells and the output bus, the switch matrix being configured to dynamically vary a power characteristic of power applied to the power output bus from the array of battery cells based on a power configuration command received at the programmable battery, an array of battery cells; a power output bus; a switch matrix coupled to the battery cells and the output bus, the switch matrix being configured to dynamically vary a power characteristic of power applied to the power output bus from the array of battery cells based on a power configuration command received at the programmable battery, wherein the power output bus of the programmable battery is coupled to power inputs, i.e. gain inputs and power supply inputs, of various subsystems and other electronic devices of the wireless communications device; and wherein conductors of the power output bus are each coupled to the power input of a respective subsystem or electronic device of the wireless communications device, whereby the programmable battery is configured to adjust the power supplied to the gain inputs and the power supply inputs of the subsystems/devices independently of each other; wherein the power output bus is coupled to the gain input (A, B) of the variable-gain power amplifier, and the programmable battery is configured to dynamically adjust the magnitude of the voltage applied to the gain input (A, B) of the variable-gain power amplifier in accordance with a power requirement of the wireless network (219, 221).