International audienceThis paper presents the design of a broadband power amplifier (PA) in 130 nm SiGe BiCMOS technology. First, a single stage broadband single cell PA covering the 4.5-18 GHz frequency band is introduced. In this frequency range, this single cell achieves a measured gain, saturated output power (Psat), output 1 dB compression point (P1dB) and power added efficiency (PAE) in the range of 12.8 to 15.7 dB, 18.8 to 23.7 dBm, 16.7 to 19.5 dBm and 11.4 to 31.9%, respectively. Its peak saturated output power and maximum PAE are both obtained at 8.5 GHz. Second, to increase the output power, a PA consisting of two parallel broadband cells with power combination is presented. This PA operates in the 4.5-15.5 GHz frequency range wi...