A radar system comprising: a pulse radar unit; a switching mode DC/DC (Direct Current/Direct Current) power converter for delivering a direct current to the pulse radar unit; and the pulse radar unit configured to transmit RF pulses with a pulse duration, wherein the switching mode DC/DC power converter comprises: a first switching element configured to be turned on and off in each switching cycle of the switching mode power converter; an inductor configured to be charged and discharged in each switching cycle of the switching mode power converter; a capacitor configured to maintain a DC output voltage as the inductor is charged and discharged each switching cycle; a second switching element arranged to close a current path to the output such that energy stored in the inductor is supplied to the output when the first switch is turned off; a control loop configured to regulate the output voltage with a time constant to a predetermined value by means of controlling the first switching element; wherein the control loop is configured to choose an on time for the said first switching element in each cycle to allow the current through the inductor to fall to zero in each cycle, characterized in that the switching cycle is shorter than the RF pulse duration and that the time constant of the control loop is longer than the RF pulses. a pulse radar unit; a switching mode DC/DC (Direct Current/Direct Current) power converter for delivering a direct current to the pulse radar unit; and the pulse radar unit configured to transmit RF pulses with a pulse duration, wherein the switching mode DC/DC power converter comprises: a first switching element configured to be turned on and off in each switching cycle of the switching mode power converter; an inductor configured to be charged and discharged in each switching cycle of the switching mode power converter; a capacitor configured to maintain a DC output voltage as the inductor is charged and discharged each switching cycle; a second switching element arranged to close a current path to the output such that energy stored in the inductor is supplied to the output when the first switch is turned off; a control loop configured to regulate the output voltage with a time constant to a predetermined value by means of controlling the first switching element; a first switching element configured to be turned on and off in each switching cycle of the switching mode power converter; an inductor configured to be charged and discharged in each switching cycle of the switching mode power converter; a capacitor configured to maintain a DC output voltage as the inductor is charged and discharged each switching cycle; a second switching element arranged to close a current path to the output such that energy stored in the inductor is supplied to the output when the first switch is turned off; a control loop configured to regulate the output voltage with a time constant to a predetermined value by means of controlling the first switching element; wherein the control loop is configured to choose an on time for the said first switching element in each cycle to allow the current through the inductor to fall to zero in each cycle, characterized in that the switching cycle is shorter than the RF pulse duration and that the time constant of the control loop is longer than the RF pulses.