| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce the cost of a noise generator by constituting the noise generator of only hardware which generates noise signal of a wideband corresponding to 'test under noise environment' in the CDMA(code division multiple access) system. SOLUTION: In a noise generator 1, a noise source A2, an amplifier A4, and a filter A6 which generate an I signal for quadrature modulation and a noise source B3, an amplifier B5, and a filter B7 which generates a Q signal for quadrature modulation are provided, and the I signal and the Q signal generated by these circuits are subjected to quadrature modulation in a quadrature modulator 8 by a local signal supplied from a local signal source 9, thus outputting a noise signal.</p> |
