Programmable power supplies for cellular base stations and related methods of reducing power loss in cellular systems
Methods of powering a radio that is mounted on a tower of a cellular base station are provided in which a direct current (“DC”) power signal is provided to the radio over a power cable and a voltage level of the output of the power supply is adjusted so as to provide a substantially constant voltage at a first end of the power cable that is remote from the power supply. Related cellular base stations and programmable power supplies are also provided.
1. A power supply system for a cellular base station, comprising:
a second power supply that has an input that is configured to receive a first direct current (“DC”) power signal from a first power supply, the second power supply comprising a DC-to-DC power supply that is configured to output to a radio via a cabling connection connected to an output of the second power supply a second DC power signal in response to the first DC power signal, and the second power supply further comprising a current sensor that is configured to measure a current of the second DC power signal,
wherein the current sensor comprises a resistance and a voltage meter that is configured to measure a voltage drop across the resistance, and
wherein the second power supply is configured to adjust a voltage of the second DC power signal as the current of the second DC power signal changes.
2. The power supply system of claim 1 , wherein the second power supply is configured to adjust the voltage of the second DC power signal based on at least one of the current of the second DC power signal or a resistance of the cabling connection that is connected to the output of the second power supply.
3. The power supply system of claim 2 , wherein the second power supply further includes a resistance determination circuit that is configured to determine the resistance of the cabling connection, and wherein the second power supply is configured to adjust the voltage of the second DC power signal based on both the current of the second DC power signal and the resistance of the cabling connection.
4. The power supply system of claim 2 , wherein the second power supply includes:
a voltage conversion circuit; and
control logic that is configured to adjust parameters of the voltage conversion circuit in response to changes in the current of the second DC power signal to set the voltage of the second DC power signal.
5. The power supply system of claim 1 , in combination with an equipment enclosure and the first power supply, wherein both the first power supply and the second power supply are within the equipment enclosure.
6. A power supply system for a cellular base station, comprising:
a power supply that has an input that is configured to receive a first direct current (“DC”) power signal and an output that is coupled to a radio via a cabling connection, the power supply configured to output a second DC power signal,
wherein the power supply is configured to adjust a voltage of the second DC power signal so that at an end of the cabling connection that is remote from the power supply the second DC power signal will have a voltage that is at least 4 Volts above a nominal power signal voltage of the radio and less than a maximum power signal voltage of the radio notwithstanding variation in a current of the second DC power signal.
7. The power supply system of claim 6 , wherein the power supply is configured to adjust the voltage of the second DC power signal based on measured variations in the current of the second DC power signal and a resistance of the cabling connection.
8. The power supply system of claim 7 , wherein the power supply includes:
a voltage conversion circuit;
control logic that is configured to adjust parameters of the voltage conversion circuit in response to changes in the current of the second DC power signal to set a voltage of the second DC power signal; and
a resistance determination circuit that is configured to determine the resistance of the cabling connection.
9. The power supply system of claim 7 , wherein the power supply includes a current sensor that is configured to measure the current of the second DC power signal.
10. The power supply system of claim 6 , in combination with an equipment enclosure, wherein the power supply and a second power supply that outputs the first DC power signal are within the equipment enclosure.
11. A power supply system for a cellular base station, comprising:
a second power supply that has an input that is configured to receive a first direct current (“DC”) power signal from a first power supply, the second power supply comprising a DC-to-DC power supply that is configured to output to a radio via a cabling connection connected to an output of the second power supply a second DC power signal in response to the first DC power signal,
wherein the second power supply is configured to adjust a voltage of the second DC power signal in response to variations in a current of the second DC power signal based on the current of the second DC power signal and based on a resistance of the cabling connection that is connected to an output of the second power supply.
12. The power supply system of claim 11 , wherein the second power supply includes:
a voltage conversion circuit configured to convert a voltage of the first DC power signal to a different voltage;
control logic that is configured to adjust parameters of the voltage conversion circuit in response to changes in the current of the second DC power signal to set the voltage of the second DC power signal; and
a resistance determination circuit that is configured to determine the resistance of the cabling connection.
13. The power supply system of claim 12 , wherein the second power supply includes a current sensor that is configured to measure the current of the second DC power signal.
14. A power supply system for a cellular base station, comprising:
a power supply that has an input that is configured to receive a first direct current (“DC”) power signal and an output that is coupled to a cabling connection, the power supply configured to output a second DC power signal,
wherein the power supply is configured to adjust a voltage of the second DC power signal so that at an end of the cabling connection that is remote from the power supply the second DC power signal will have a substantially constant voltage notwithstanding variation in a current of the second DC power signal, and
wherein the substantially constant voltage of the second DC power signal exceeds a nominal power signal voltage of a radio coupled to the end of the cabling connection that is remote from the power supply so as to reduce power loss in the cabling connection as compared to the power loss that occurs in the cabling connection when the DC power signal at the end of the cabling connection that is remote from the power supply is at the nominal power signal voltage.
15. The power supply system of claim 14 , wherein the substantially constant voltage is within 4 Volts of a maximum power signal voltage of a radio coupled to the end of the cabling connection that is remote from the power supply.
16. The power supply system of claim 14 , wherein the substantially constant voltage is at least 4 Volts above the nominal power signal voltage of a radio coupled to the end of the cabling connection that is remote from the power supply and less than a maximum power signal voltage of the radio.