Method for receiving a multi-carrier radio frequency (RF) signal and RF receiver

Abstract

The invention relates generally to a method and an arrangement for receiving a radio frequency (RF) signal and an RF receiver. Particularly the invention relates to controlling and reducing power consumption in a radio receiver. The invention can advantageously be applied in receiving arrangements of radio systems, wherein information is transferred in bursts, such as a receiver of Digital Video Broadcasting (DVB) system. According to the invention, during the time between two bursts the power supply is maintained in at least in some parts of the phase locked loop PLL, while one or several other parts of the receiver are turned off for a certain time period between the two bursts. The present invention enables fast tuner lock-in time and still offers a considerable saving in total power consumption of the receiver.

1 . A method for receiving radio frequency signals that include modulated information, wherein the radio frequency signals comprises multi-carrier radio frequency signals and the method comprises a step for maintaining a power of at least one part of a powered receiver while turning off the power from another receiver part depending on a state of a transmission of the multi-carrier radio frequency signals.  
     
     
         2 . A method according to  claim 1 , further comprising the step of applying a power down pin for switching down at least one of a phase locked loop, a step up converter and a demodulator.  
     
     
         3 . A method for receiving multi-carrier radio frequency signals that appear as bursts, and the method further comprising the steps of: 
 providing a local frequency signal with an oscillator,    controlling the frequency of the oscillator with a phase locked loop,    mixing the input signal of the multi-carrier radio frequency signal with the local frequency signal for producing an intermediate frequency signal,    demodulating the intermediate frequency signal for producing a data stream of the information, and    supplying power for receiver means providing the method steps,    turning off the supply power of the receiver means for supplying continuous power to at least one part of the receiver means that provides the step of demodulation, and    turning off the supply power from another receiver part of the receiver means for a determined period of time in accordance with the bursts.    
     
     
         4 . A method according to  claim 3 , wherein a low voltage power is received from a battery.  
     
     
         5 . A method according to  claim 4 , wherein an operating power is lead to the phase locked loop directly from said battery.  
     
     
         6 . A method according to  claim 4 , wherein the voltage of said battery is converted to a higher value with at least one step up converter and the supply power of said higher voltage value is used to give power to at least one of said receiver parts.  
     
     
         7 . A method according to  claim 6 , wherein the said conversion is turned off for a determined period of time between receiving two consecutive bursts.  
     
     
         8 . A method according to  claim 7 , wherein the voltage of said battery is converted to a second higher value with a step up converter and the supply power of said higher voltage value is used for producing the output voltage of the phase locked loop, and said conversion is turned off for a determined period of time between receiving two consecutive bursts.  
     
     
         9 . A method according to  claim 3 , wherein a threshold value is determined for the voltage of supply power for at least one of the receiver parts, the voltage of the supply power is sensed in said at least one receiver part, and the operation of said receiver part is internally turned off when the value of said supply voltage is lower than said determined threshold value for the supply voltage.  
     
     
         10 . A method according to  claim 3 , further comprising the step of applying a power down pin IC for turning down at least one of the phase locked loop, a step up converter and the demodulator.  
     
     
         11 . A receiver for receiving and processing radio frequency signals that include modulated information, wherein the radio frequency signals comprises multi-carrier radio frequency signals and the receiver comprises means for keeping at least a part of the receiver powered depending on a state of a transmission of the multi-carrier radio frequency signals, and a controller for turning off supply power from another receiver part for a determined time depending on the state of the transmission.  
     
     
         12 . A receiver according to  claim 11 , further comprising a power down pin for switching down at least one of a phase locked loop, a step up converter and a demodulator.  
     
     
         13 . A receiver for receiving multi-carrier radio frequency signals, which appear as bursts, and the receiver further comprising: 
 an oscillator for producing a local frequency signal,    a phase locked loop for controlling the frequency of the local frequency signal,    a mixer for mixing the input signal of the multi-carrier radio frequency signals with the local frequency signal for producing an intermediate frequency signal,    a demodulator for producing a data stream of said information,    a power supply for supplying power for the receiver,    means for keeping at least a part of the phase locked loop powered during a period between two consecutive bursts to be received, and    a controller for turning off the supply power from another receiver part for a determined time during the period between two consecutive bursts to be received.    
     
     
         14 . A receiver according to  claim 13 , wherein said power supply comprises a battery for providing low voltage power.  
     
     
         15 . A receiver according to  claim 14 , wherein the battery is arranged to supply power directly to the phase locked loop.  
     
     
         16 . A receiver according to  claim 14 , wherein the battery is arranged to supply power directly to the demodulator.  
     
     
         17 . A receiver according to  claim 14 , wherein the power supply comprises at least one step up converter for providing power of higher voltage from the low voltage power of the battery.  
     
     
         18 . A receiver according to  claim 17 , wherein a first step up converter is arranged to provide power for at least one of following receiver parts, an input amplifier, the mixer, and the oscillator.  
     
     
         19 . A receiver according to  claim 18 , wherein the receiver comprises means for turning off the first step-up converter for a determined time during said period between two consecutive bursts to be received.  
     
     
         20 . A receiver according to  claim 17 , wherein a second step up converter is arranged to provide power for the phase locked loop for producing the control signal for the oscillator.  
     
     
         21 . A receiver according to  claim 20 , wherein the receiver comprises means for turning off said second step-up converter for a determined time during said period between two consecutive bursts to be received.  
     
     
         22 . A receiver according to  claim 13 , wherein the oscillator is a voltage controlled oscillator.  
     
     
         23 . A receiver according to  claim 13 , wherein the receiver comprises means for turning off the demodulator for a determined time during the period between two consecutive bursts to be received.  
     
     
         24 . A receiver according to  claim 13 , wherein at least one of the receiver parts comprises means for sensing a voltage of its supply power, and means for turning off the operation of the receiver part when the value of the supply voltage is lower than a determined threshold value for the supply voltage.  
     
     
         25 . A receiver according to  claim 13 , wherein the receiver further comprises a power down pin IC for turning down at least one of the phase locked loop, a step up converter and the demodulator.  
     
     
         26 . The method of  claim 1 , wherein the multi-carrier radio frequency signals comprise DVB radio frequency signals.  
     
     
         27 . The method of  claim 3 , wherein the multi-carrier radio frequency signals comprise DVB radio frequency signals.  
     
     
         28 . The receiver of  claim 11 , wherein the multi-carrier radio frequency signals comprise DVB radio frequency signals.  
     
     
         29 . The receiver of  claim 13 , wherein the multi-carrier radio frequency signals comprise DVB radio frequency signals.