Methods and apparatuses for converting DC voltages

Abstract

In one embodiment, an integrated power cable is provided. The integrated power cable, comprises a power cable having a first end and a second end; wherein the first end is configured to be electrically coupled to a DC power supply; at least one DC-DC voltage converter having at least one input and at least one output; wherein the second end is fixedly electrically and mechanically connected to the input; a first connector fixedly connected mechanically and electrically to the output; and wherein the first connector is configured to be coupled to at least one remote radio head.

The invention claimed is: 
     
       1. An apparatus, comprising:
 an enclosure configured to be mounted on a mounting structure; 
 at least one DC-DC voltage converter, in the enclosure, having a converter power input configured to receive a first voltage between 380V and 400V and a converter power output configured to provide between 3.3V and 48V a second voltage; 
 at least one front end of a radio, in the enclosure, having a front end power input coupled to the converter power output; 
 wherein the converter power input is further configured to be coupled to a first end of a power cable; and 
 communications circuitry, in the enclosure, configured to communicate with safety circuitry configured to provide the first voltage between 380V and 400V to a second end of the power cable only upon receipt of a signal from the communications circuitry, wherein the first voltage is larger than the second voltage. 
 
     
     
       2. The apparatus of  claim 1 , wherein the at least one DC-DC voltage converter comprises a synchronous step-down converter. 
     
     
       3. The apparatus of  claim 1 , wherein the each front end comprises at least one of a low noise amplifier, a power amplifier, an upconverter, and a downconverter. 
     
     
       4. The apparatus of  claim 1 , wherein the mounting structure is a tower. 
     
     
       5. The apparatus of  claim 1 , further comprising low voltage conversion circuitry configured to receive the first voltage between 380V and 400V and to provide a lower voltage to the at least one DC-DC voltage converter. 
     
     
       6. The apparatus of  claim 1 , further comprising a battery backup system;
 wherein the safety circuitry comprises a redundancy system; and   wherein the redundancy system is coupled the battery backup system.   
     
     
       7. A method, comprising:
 starting a safety system comprising a voltage output; 
 providing a first voltage at the voltage output of the safety system, where the first voltage is configured to power communications circuitry of a radio system, where the radio system is coupled to the voltage output by a power cable, where the radio system comprises an enclosure, the communications circuitry, the at least one DC-DC voltage converter, and at least one radio front end, where the at least one DC-DC voltage converter is coupled to the at least one radio front end, where the enclosure contains at least the at least one DC-DC voltage converter and at least one radio front end, and where the radio system is configured to be mounted on a mounting structure; 
 initiating communications between the safety system and the communications circuitry; 
 determining if communications between the safety system and the communications circuitry have been established; and 
 if communications have been establishedestablishing communications between the safety system and the communications circuitry by the safety system's receipt of a signal from the communications circuitry, then providing at the voltage output between 380V and 400Va second voltage, wherein the second voltage is larger than the first voltage. 
 
     
     
       8. The method of  claim 7 , further comprising determining if the safety system started properly. 
     
     
       9. The method of  claim 8 , wherein determining if the safety system started properly comprises determining if the voltage output is short circuited. 
     
     
       10. The method of  claim 8 , further comprising if the safety system is determined not to have started properly, then restart the safety system. 
     
     
       11. The method of  claim 10 , further comprising starting a timer which runs for a time period; and
 after the time period ends, then restarting the safety system. 
 
     
     
       12. The method of  claim 7 , wherein initiating the communications between the safety system and the communications circuitry comprises sending a query message from the safety system to the communications circuitry. 
     
     
       13. The method of  claim 7 , wherein determining if the communications between the safety system and the communications circuitry have been established comprises determining if at least one acknowledgement message was received from the communications circuitry. 
     
     
       14. A power cable An apparatus, comprising:
 a power cable having a first end and a second end, where the first end is opposite the second end, and where the first end is configured to be electrically coupled to a DC power supply; 
 at least one DC-DC voltage converter having at least one converter input and at least one converter output, where the at least one converter input is fixedly electrically and mechanically connected to the second end, where the at least one converter input is configured to receive a voltage between 380V and 400V, and where the at least one converter output is configured to provide a lower voltage configured to power at least one radio; 
 a first connector fixedly electrically and mechanically connected to the at least one converter output; 
 wherein the at least one DC-DC voltage converter, a portion of the first connector, and the second end are covered by an insulator; and 
 where the first connector is configured to be coupled to a power input of the at least one radio mounted on a mounting structure. 
 
     
     
       15. The power cable apparatus of  claim 14 , wherein the insulator is heat shrink material. 
     
     
       16. The power cable apparatus of  claim 14 , wherein the at least one DC-DC voltage converter comprises a synchronous step-down converter. 
     
     
       17. The power cable apparatus of  claim 14 , wherein the at least one DC-DC voltage converter comprises communications circuitry configured to communicate with safety circuitry, where the safety circuitry is configured to provide a voltage between 380V and 400V from the DC power supply to a the second end of the power cable only upon receipt of a signal from the communications circuitry. 
     
     
       18. The power cable apparatus of  claim 14 , wherein the at least one radio comprises at least one remote radio head. 
     
     
       19. The power cable of  claim 14 , wherein the mounting structure comprises a tower. 
     
     
       20. The apparatus of  claim 1 , wherein the first voltage is between 380V and 400V. 
     
     
       21. The apparatus of  claim 1 , wherein the second voltage is between 3.3V and 48V. 
     
     
       22. The method of  claim 7 , wherein the second voltage is between 380V and 400V.