| 摘要 |
PURPOSE:To avoid the problem of saturation in a D range or a beam former at the time of a CW Doppler mode by executing a signal processing by an IF system at the time of an imaging mode, and executing a signal processing by a base band system at the time of the CW Doppler mode. CONSTITUTION:When the device functions as an IF beam former in the case of operating in an imaging mode, outputs of A/D converters 19, 20 are inputted to combination of digital Hilbert converter 32 and a combiner 33 for constituting a digital phase shifter 31, and matching of the phases is executed. Thereafter, an output of the combiner 33 is delayed for a prescribed time by a variable delaying circuit 34, and thereafter, added together with a signal from other channel inputted to an addition synthesizer 35, and brought to delay addition. On the other hand, in the case of a CW Doppler mode, the processing can be executed by only the digital Hilbert converter 32 and the combiner 33. However, in this case, the Hilbert transformation which can be applied for audio use, as well becomes long as to its sample section length, but it is executed by a DSP together with a built-in decimation filter, or it is possible to cope therewith suitably by executing it only analogously. |
