Introduction:

The Doppler blood measuring device we developed can equip with 2mhz, 4mhz, 8mhz blood flow sensor to measure the different depth blood flow rate. The output interface is USB port, and input the power is standard PC power. There could offer some sort of raw data or the calculated data as Vp; Vm, Vd, PI, RI, SD, Hr.  Besides, we could offer the output as bitmap spectrum when connect with your laptop or PC directly.

The technical requirements stipulate the main technical requirements of the unit pulse wave type (PW) and the dual-wafer separation continuous wave type (CW) ultrasonic Doppler probes, as the basis for technical inspection and evaluation.

4MHz Craniocervical Doppler probe:

Technology parameters:                                                                      

1. Main content and scope of application:

 The technical requirements stipulate the main technical requirements of the unit pulse wave type (PW) and the dual-wafer separating continuous wave type (CW) ultrasonic doppler probes, as the basis for technical inspection and evaluation.

2. Reference Standard:

ZBC41010 unit pulse - general technical requirements and measurement methods for echo ultrasonic transducers.

GB6385  safety specific requirements of ultrasonic diagnostic equipment.

3. Terms, symbols:

3.1 Working frequency fo

The frequency corresponding to the peak value of the doppler transducer and frequency response curve consisting of a unit or a transmit-receive wafer, unit: MHz

3.2 Relative bandwidth △f/fo

In the frequency response curve referred to in 3.1, the ratio of the difference between the high and low frequencies fh and fl (Δf ) and fo corresponding to the 6dB drop on the optimum frequency fo

   Δf / fo = (fh―fl) /fo*100% unit %

3.3 Relative sensitivity

The number of decibels in the ratio of the signal voltage Vt applied to the transmitting wafer to the output voltage Vr on the receiving wafer under the specified reflecting target

   Mtr=20logVr/Vt unit dB

(For a unit pulsed transducer, the number of decibels in the ratio of Vt to Vr on the same wafer)

3.4 sending-receiving signal mix Mc

The number of decibels in the ratio of the signal voltage Vt applied to the emitting wafer to the output voltage Vr on the receiving wafer when the transducer is unloaded.

That is: Mc=20logVr/Vt unit dB

4. Technical requirements:

4.1 PW ultrasonic transducer:

4.1.1 Operating frequency (fo): 2MHZ±0.2MHZ

4.1.2 Static capacitance (Co): 2300PF ± 15%

4.1.3 Relative bandwidth (△f/fo): ≥30%

4.1.4 Relative sensitivity (Mtr): better than -8dB

4.2 CW ultrasonic transducer (4MHZ):

4.2.1 Operating frequency (fo): 4MHZ±0.4MHZ

4.2.2 Static capacitance (Co): 1200 PF ± 15% for each of the transmitting and receiving.

4.2.3 Relative bandwidth (△f/fo): ≥15%

4.2.4 Relative sensitivity (Mtr): better than -20dB

4.2.5 Transmitting and Receiving Signal Mixing (Mc): < -50dB

4.3 CW Ultrasound Transducer (8MHZ)

4.3.1 Operating frequency (fo): 8MHZ±0.8MHZ

4.3.2 Static capacitance (Co): The transmitting-receiving is 500PF±15% .

4.3.3 Relative bandwidth (△f/fo): ≥20%

4.3.4 Relative sensitivity (Mtr): better than -15dB

4.3.5 Transmitting and Receiving Signal Mixing (Mc): < -50dB