c*****s
发帖数: 184 | 1 大功率放大器？用什么样的管子？对线性要求高不
还请大牛们指点一下或者推荐一些参考资料
多谢多谢 | p*****t
发帖数: 966 | 2 LDMOS or GaN high power transistor | B*****2
发帖数: 83 | 3 In MR, my understanding is to keep the heating effect as small as
possible. Thus, LDMOS or GaN high power transistor, not necessary.
【在 p*****t 的大作中提到】
: LDMOS or GaN high power transistor
| p*****t
发帖数: 966 | 4 then how to get high power and low cost?
LDMOS is the best choice. | B*****2
发帖数: 83 | 5 What is the frequency range? To my experiments, I scanned the frequency
from 1 GHz to 20 GHz. Only very few amplifiers, such as an amplifier from
Agilent (used YIG oscillations), could be used. The power is limited to 1W
in order not to heat the samples, the 线性 is not required because it is
just a source, but high stability is required. During the scanning H
field, it should be very stable, so that we could detect the absorption
and reflection.
【在 c*****s 的大作中提到】
: 大功率放大器？用什么样的管子？对线性要求高不
: 还请大牛们指点一下或者推荐一些参考资料
: 多谢多谢
| c*****s
发帖数: 184 | 6 Analogic RF Power Amplifiers for MRI can get power levels up to 36 kW!
http://www.analogic.com/products-medical-magnetic-resonance-imaging-rf-
amps.htm
I guess LDMOS is the only choice for this case?
【在 p*****t 的大作中提到】
: LDMOS or GaN high power transistor
| c*****s
发帖数: 184 | 7 about few hundred MHz. just one more question, would strong magnetic field
(1.5T-3T) disturb rf signal?
from
1W
【在 B*****2 的大作中提到】
: What is the frequency range? To my experiments, I scanned the frequency
: from 1 GHz to 20 GHz. Only very few amplifiers, such as an amplifier from
: Agilent (used YIG oscillations), could be used. The power is limited to 1W
: in order not to heat the samples, the 线性 is not required because it is
: just a source, but high stability is required. During the scanning H
: field, it should be very stable, so that we could detect the absorption
: and reflection.
| B*****2
发帖数: 83 | 8 I didn't realize that it is for MRI, and thought MR for lab experiment,
and for a small sample.
If it is 36 kW, I guess it is hard even for LDMOS and power combiner is
hard to design. The cheapest way is to buy a magnetron, a similar vaccum
tube as in microwave oven.
【在 c*****s 的大作中提到】
: Analogic RF Power Amplifiers for MRI can get power levels up to 36 kW!
: http://www.analogic.com/products-medical-magnetic-resonance-imaging-rf-
: amps.htm
: I guess LDMOS is the only choice for this case?
|
| c*****s
发帖数: 184 | 9 谢谢
我没有把问题表述清楚，抱歉:)
【在 B*****2 的大作中提到】
: I didn't realize that it is for MRI, and thought MR for lab experiment,
: and for a small sample.
: If it is 36 kW, I guess it is hard even for LDMOS and power combiner is
: hard to design. The cheapest way is to buy a magnetron, a similar vaccum
: tube as in microwave oven.
|
|
