JPS6226710B2 - - Google Patents
Info
- Publication number
- JPS6226710B2 JPS6226710B2 JP8890781A JP8890781A JPS6226710B2 JP S6226710 B2 JPS6226710 B2 JP S6226710B2 JP 8890781 A JP8890781 A JP 8890781A JP 8890781 A JP8890781 A JP 8890781A JP S6226710 B2 JPS6226710 B2 JP S6226710B2
- Authority
- JP
- Japan
- Prior art keywords
- switching
- signal
- power
- measured
- pulse
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 230000001360 synchronised effect Effects 0.000 claims description 12
- 238000010586 diagram Methods 0.000 description 9
- 238000000034 method Methods 0.000 description 9
- 238000005259 measurement Methods 0.000 description 3
- 238000007796 conventional method Methods 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000284 extract Substances 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R29/00—Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
- G01R29/08—Measuring electromagnetic field characteristics
- G01R29/0864—Measuring electromagnetic field characteristics characterised by constructional or functional features
- G01R29/0871—Complete apparatus or systems; circuits, e.g. receivers or amplifiers
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- General Physics & Mathematics (AREA)
- Indication And Recording Devices For Special Purposes And Tariff Metering Devices (AREA)
- Radiation Pyrometers (AREA)
Description
【発明の詳細な説明】
本発明は、電波天文やアンテナ特性の測定及び
リモートセンシングなどの分野で広く使用され
る、微弱な信号を安定にかつ高感度に計測できる
ラジオメータに関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a radiometer that is widely used in fields such as radio astronomy, measurement of antenna characteristics, and remote sensing, and is capable of stably and highly sensitively measuring weak signals.
従来から広く用いられているデイツケ式ラジオ
メータにおいて、バランス型でない場合は受信系
の利得の変動の影響を除くため、ひん繁に校正を
行う必要があつた。また、零バランス型の場合
は、利得変動の影響はないが、被測定側又は基準
側に両者の電力が等しくなるように注入される付
加信号源を必要とし、回路系が複雑で、被測定範
囲が制限され、かつ、受信機入力動作雑音電力が
高いなどの欠点があつた。本発明はこれらの欠点
を克服したもので、以下図面を参照しながら説明
する。第１図は従来公知のデイツケ式ラジオメー
タの基本的な構成例で、１は被測定対象に指向さ
れるアンテナ、２は基準雑音源、３は被測定側と
基準側を切り換えるサーキユレータスイツチ、４
はアイソレータ、５は局部発振器、６は前置増幅
器と周波数変換器、７は帯域通過フイルター、８
は中間周波増幅器、９は２乗検波器、１０はアン
テナ側と基準側の差をとり出す同期検波器、１１
は積分器、１２は切換え信号用発振器、１３はサ
ーキユレータスイツチ３を駆動するスイツチ駆動
電源である。信号線Ｓ，Ｃ，Ｄ，V0，Ｔa，Ｔrは
それぞれ、スイツチ切換え信号、同期信号、２乗
検波器出力信号、積分器出力電圧、被測定電力、
基準電力である。第１図の積分器出力電圧V0
は、受信系の全利得をＧ，Ｋを定数として次式で
表わす。 In Deitzke radiometers that have been widely used in the past, if they are not a balanced type, it is necessary to frequently calibrate them in order to remove the influence of fluctuations in the gain of the receiving system. In addition, in the case of the zero-balanced type, although there is no effect of gain fluctuation, it requires an additional signal source to be injected into the measured side or the reference side so that the power of both sides is equal, and the circuit system is complex. The disadvantages were that the range was limited and the receiver input operating noise power was high. The present invention overcomes these drawbacks and will be described below with reference to the drawings. Figure 1 shows an example of the basic configuration of a conventionally known Deitzke radiometer, in which 1 is an antenna directed toward the object to be measured, 2 is a reference noise source, and 3 is a circulator switch that switches between the measured side and the reference side. , 4
is an isolator, 5 is a local oscillator, 6 is a preamplifier and frequency converter, 7 is a bandpass filter, 8
is an intermediate frequency amplifier, 9 is a square law detector, 10 is a synchronous detector that extracts the difference between the antenna side and the reference side, 11
12 is an integrator, 12 is a switching signal oscillator, and 13 is a switch drive power source for driving the circulator switch 3. The signal lines S, C, D, V 0 , T a , and T r respectively carry a switch switching signal, a synchronization signal, a square-law detector output signal, an integrator output voltage, a measured power,
This is the reference power. Integrator output voltage V 0 in Figure 1
The total gain of the receiving system is expressed by the following equation, where G and K are constants.
V0＝Ｋ・Ｇ（Ｔr―Ｔa） ……(1)
したがつて、ＴrとＴaが等しくない限り、利得
Ｇに変動があると、被測定電力Ｔaに変動がなく
ても、V0は変動し、不安定な出力となる。この
欠点を改良したのが、第２図の例に示した零バラ
ンス型ラジオメータで、(1)式において被測定電力
Ｔaと基準電力Ｔrを等しく保つと利得Ｇが変動し
ても、利得Ｇに関係なく積分器出力電圧V0は常
に零となることを利用したものである。第２図
で、アンテナ１からスイツチ駆動電源１３までの
符号は第１図と同じであるが、積分器出力電圧
V0をサーボ増幅器１４に入力し、そのサーボ増
幅器出力電圧Ｔをパルス変調器１５に入力し、さ
らにスイツチ切換え信号Ｓに同期したパルス変調
器１５のパルス出力信号から、雑音源駆動電源１
６によつてバランス用付加雑音源１７で作られた
パルス状雑音電力Ｔoを、結合器１８を通して被
測定電力Ｔaに付加し、それらの平均電力が基準
電力Ｔrに等しくバランスさせると、積分器出力
電圧V0は零となる。しがつて、積分器出力電圧
V0が常に零になるようにサーボ増幅器出力電圧
Ｔでパルス状付加雑音電力を制御すれば、利得変
動の影響を受けずに被測定電力Ｔaをサーボ増幅
器出力電圧Ｔから求めることができる。パルス状
付加雑音電力の制御方法には、パルス周波数変調
方式やパルス幅変調方式があるが、その後者の例
として、第２図のパルス変調器１５にパルス幅変
調器を用いた時の２乗検波器出力信号Ｄを第３図
に示した。第３図において、Ｓa，Ｓrはサーキユ
レータスイツチ３がそれぞれ被測定側、基準側に
なつていることを示し、ｔoは付加されるパルス
状雑音電力Ｔoのパルス幅を示す。従来方式では
第３図で、サーキユレータスイツチ３が被測定側
（Ｓa）と基準側（Ｓr）になつている間のスイツ
チ切換え時間ｔsは常に等しいから、両側でのエ
ネルギーが等しいというバランス条件は次式とな
る。 V 0 =K・G(T r −T a ) ...(1) Therefore, unless T r and T a are equal, if there is a change in the gain G, there will be no change in the measured power T a. However, V 0 fluctuates, resulting in unstable output. This drawback has been improved by the zero-balance radiometer shown in the example in Figure 2. In equation (1), if the measured power T a and the reference power T r are kept equal, even if the gain G varies, This takes advantage of the fact that the integrator output voltage V 0 is always zero regardless of the gain G. In Figure 2, the symbols from antenna 1 to switch drive power supply 13 are the same as in Figure 1, but the integrator output voltage
V 0 is input to the servo amplifier 14, the servo amplifier output voltage T is input to the pulse modulator 15, and from the pulse output signal of the pulse modulator 15 synchronized with the switch switching signal S, the noise source driving power supply 1
6, the pulsed noise power T o generated by the balancing additional noise source 17 is added to the measured power T a through the coupler 18, and the average power thereof is balanced to be equal to the reference power T r . The integrator output voltage V 0 becomes zero. Therefore, the integrator output voltage
If the pulsed additional noise power is controlled by the servo amplifier output voltage T so that V 0 is always zero, the measured power T a can be determined from the servo amplifier output voltage T without being affected by gain fluctuations. There are pulse frequency modulation methods and pulse width modulation methods to control the pulsed additional noise power, and as an example of the latter, the square modulation method when a pulse width modulator is used as the pulse modulator 15 in FIG. The detector output signal D is shown in FIG. In FIG. 3, S a and S r indicate that the circulator switch 3 is on the measured side and the reference side, respectively, and t o indicates the pulse width of the added pulsed noise power T o . In the conventional method, as shown in Fig. 3, the switching time t s between the circulator switch 3 being set to the measured side (S a ) and the reference side (S r ) is always equal, so the energy on both sides is equal. The balance condition is as follows.
Ｔa・ｔs＋Ｔo・ｔo＝Ｔr・ｔs ……(2)
(2)式で、Ｔr、Ｔo、ｔsを一定値とすれば、被
測定電力Ｔaとパルス状雑音電力Ｔoのパルス幅ｔ
oは比例するから、常に(2)式が成立するようにパ
ルス幅ｔoを制御すれば、その制御電圧（サーボ
増幅器出力電圧Ｔ）がラジオメータの出力とな
る。従来の零バランス方式は、第３図又は(2)式か
らも明らかなように、被測定電力Ｔaは基準電力
Ｔrを越えることはできないから、被測定電力Ｔa
が制限され、かつ、基準電力Ｔrを高くとらざる
を得ないため、動作点での雑音電力が高く、出力
のゆらぎの増加をもたらすなどの欠点があつた。
また、第２図に示すようにバランス用付加雑音源
１７や結合器１８が不可欠で、回路系が複雑とな
り、給電損失の増加などの欠点がある。 T a・t s + T o・t o = T r・t s ...(2) In equation (2), if T r , T o , and t s are constant values, the measured power T a and the pulsed Pulse width t of noise power T o
Since o is proportional, if the pulse width t o is controlled so that equation (2) always holds true, the control voltage (servo amplifier output voltage T) becomes the output of the radiometer. In the conventional zero balance method, as is clear from FIG. 3 or equation (2), the measured power T a cannot exceed the reference power T r , so the measured power T a
is limited and the reference power T r has to be set high, which has disadvantages such as high noise power at the operating point and increased output fluctuation.
Furthermore, as shown in FIG. 2, an additional balancing noise source 17 and a coupler 18 are essential, which complicates the circuit system and has drawbacks such as an increase in power supply loss.
本発明の目的は、バランス用付加雑音源１７な
どを必要としない簡単な回路で、かつ、バランス
を保つことにある。これは第４図に示すように、
被測定電力Ｔaと基準電力Ｔrにサーキユレータス
イツチが切り換えられている時間をそれぞれｔ
a、ｔrと異なるようにすることによつて実現され
る。この発明によるバランスの条件は次式とな
る。 An object of the present invention is to maintain balance with a simple circuit that does not require an additional noise source 17 for balancing. This is shown in Figure 4,
The time during which the circulator switch is switched to the measured power T a and the reference power T r is t, respectively.
This is achieved by making a and t r different. The balance condition according to this invention is as follows.
Ｔa・ｔa＝Ｔr・ｔr ……(3)
(3)式において、基準電力Ｔrと被測定側時間ｔa
を一定とすれば、被測定電力Ｔaと基準側時間ｔr
は比例関係となるから、被測定電力Ｔaに応じて
基準側時間ｔrをパルス幅変調器で制御すれば、
バランスを常に保つことができ、基準側時間ｔr
から被測定電力Ｔaを求めることができる。第４
図においてはＴa＜Ｔrの場合で、(3)式が成立する
からｔr＜ｔaとなるが、第５図のようにＴa＝Ｔr
となると、ｔr＝ｔaで、第６図のようにＴa＜Ｔr
の場合はｔr＞ｔaとなる。したがつて、本発明に
よれば被測定電力Ｔaは基準電力Ｔrより大きくな
つても測定できることになる。また、従来の零バ
ランス型のようにバランスする電力が一定でな
く、バランスする電力が自動的に追尾される。次
に、本発明の他の方法として、(3)式でＴrとｔrを
一定に保つこともでき、この場合はＴaとｔaは逆
比例の関係となるが、ｔaを前の例と同様にパル
ス幅変調すれば本発明の目的は達せられ、その原
理模式図を第７図に第４図と同じｔrとした場合
の例で示した。また、(3)式でｔaとｔrを一定に保
ち、Ｔaに応じＴrを制御することも可能である
が、ここでは本発明の代表例として第４図から第
６図に示した、Ｔrとｔaを一定に保つ方法につい
て述べる。第８図に本発明の実施例を示す。第８
図において、アンテナ１からサーボ増幅器１４ま
でに用いた符号は第２図と同様で、第２図のバラ
ンス用付加雑音源１７に関する１６から１８まで
不要となり、切換え信号用発振器１２とパルス変
調器１５の代わりに、切換え信号発生器２０を使
用し、第２図に比べ回路構成が簡単化されてい
る。また、本発明では、切換え波形が第４図に示
すように非対称の場合が多いので、第８図の同期
検波器１０は非対称の同期検波を行うことが必要
で、これを可能にする同期検波器１０の例を第９
図に示す。なお、Ｉは同期検波器出力信号であ
る。第９図において、２乗検波器９からの出力信
号Ｄを入力とし、増幅器３１で増幅したのち、そ
の出力を二つに分波し、その一つを増幅度が−１
である反転単位増幅器３２を通し、残りの一つの
信号とともにアナログスイツチ３３に入力する。
アナログスイツチ３３では、切換え信号発生器２
０からの非対称な同期信号Ｃによつて、これら二
つの入力信号が同期検波される。また、切換え信
号発生器２０の内部で作られるスイツチ切換え信
号Ｓを生成する回路例を第１０図に、また、その
波形生成図を第１１図に示す。これらの図におい
て、まず、ワンシヨツトマルチバイブレータ２５
で、被測定側トリガーパルスＰaによつて一定幅
（ｔa）の被測定側矩形波Ａが作られる。次に基準
側トリガーパルス発生器２２によつて、被測定側
矩形波Ａの立上りエツヂから基準側トリガーパル
スＰrが作られ、この基準側トリガーパルスＰrに
よつて、サーボ増幅器出力電圧Ｔに比例したパル
ス幅（ｔr）の基準側パルスＲがパルス幅変調器
２１で生成される。この基準側パルスＲの立下り
エツヂから被測定側トリガーパルス発生器２４
で、被測定側トリガーパルスＰaが作られ、これ
で最初の出発点に戻る。このようにして順次でき
た被測定側矩形波Ａと基準側パルスＲから、アン
ドゲート２３でスイツチ切換え信号Ｓが生成され
る。なお、第１１図中の下向矢印（↓）は、トリ
ガーのかかる方向、すなわち、波形の生成される
順序を示している。 T a・t a =T r・t r ...(3) In equation (3), the reference power T r and the measured side time t a
Assuming that is constant, the measured power T a and the reference side time t r
is a proportional relationship, so if the reference side time t r is controlled by a pulse width modulator according to the measured power T a , then
The balance can be maintained at all times, and the reference side time t r
The power to be measured T a can be obtained from . Fourth
In the figure, the case is T a < T r , and since equation (3) holds true, t r < t a , but as shown in Figure 5, T a = T r
Then, t r = t a and T a <T r as shown in Figure 6.
In this case, t r >t a . Therefore, according to the present invention, it is possible to measure even if the power to be measured T a is larger than the reference power T r . Furthermore, unlike the conventional zero balance type, the balanced power is not constant, but the balanced power is automatically tracked. Next, as another method of the present invention, it is also possible to keep T r and t r constant in equation (3). In this case, T a and t a are inversely proportional, but t a is The object of the present invention can be achieved by performing pulse width modulation in the same manner as in the example above, and a schematic diagram of its principle is shown in FIG. 7 using an example in which t r is the same as in FIG. 4. It is also possible to keep t a and t r constant using equation (3) and control T r according to T a , but here, as a representative example of the present invention, as shown in FIGS. In addition, we will discuss how to keep T r and t a constant. FIG. 8 shows an embodiment of the present invention. 8th
In the figure, the symbols used from the antenna 1 to the servo amplifier 14 are the same as in FIG. Instead, a switching signal generator 20 is used, and the circuit configuration is simplified compared to that in FIG. Furthermore, in the present invention, since the switching waveform is often asymmetrical as shown in FIG. 4, the synchronous detector 10 shown in FIG. 8 is required to perform asymmetrical synchronous detection. The example of container 10 is the 9th example.
As shown in the figure. Note that I is a synchronous detector output signal. In FIG. 9, the output signal D from the square-law detector 9 is input, and after being amplified by the amplifier 31, the output is split into two parts, one of which has an amplification degree of -1.
The signal passes through an inverting unit amplifier 32 and is input to an analog switch 33 along with the remaining signal.
In the analog switch 33, the switching signal generator 2
These two input signals are synchronously detected by the asymmetric synchronization signal C from 0. Further, an example of a circuit for generating the switch switching signal S generated inside the switching signal generator 20 is shown in FIG. 10, and a waveform generation diagram thereof is shown in FIG. In these figures, first, the one-shot multivibrator 25
A measured side rectangular wave A having a constant width (t a ) is generated by the measured side trigger pulse P a . Next, the reference side trigger pulse generator 22 generates a reference side trigger pulse P r from the rising edge of the square wave A to be measured, and this reference side trigger pulse P r causes the servo amplifier output voltage T to be A reference side pulse R having a proportional pulse width (t r ) is generated by the pulse width modulator 21 . From the falling edge of this reference side pulse R, the trigger pulse generator 24 on the measured side
Then, a trigger pulse P a on the side to be measured is generated, and the process returns to the initial starting point. A switch switching signal S is generated by the AND gate 23 from the rectangular wave A on the measured side and the pulse R on the reference side sequentially generated in this manner. Note that the downward arrow (↓) in FIG. 11 indicates the direction in which the trigger is applied, that is, the order in which the waveforms are generated.
以上示したように、本発明を実施する上で新た
に必要とされる切換え信号発生器２０や、非対称
同期検波も比較的簡単な回路で構成でき、本発明
の実施例である第８図は、従来公知の第２図に比
べて単純化されている上、さらに、その欠点を解
決している。このように本発明によれば、単純な
回路構成で、測定範囲が広く、動作雑音が低く高
感度で、より高性能であるので応用範囲も広い。 As shown above, the switching signal generator 20 and asymmetric synchronous detection, which are newly required to implement the present invention, can be constructed with relatively simple circuits, and FIG. 8, which is an embodiment of the present invention, , which is simpler than the conventionally known FIG. 2, and also solves its drawbacks. As described above, the present invention has a simple circuit configuration, a wide measurement range, low operating noise, high sensitivity, and higher performance, so it has a wide range of applications.
第１図は従来公知のデイツケ式ラジオメータの
基本的なブロツク図の例。第２図は従来公知の零
バランス式ラジオメータのブロツク図の例。第３
図は第２図でパルス幅変調方式の場合の動作原理
の模式図。第４図、第５図、第６図、第７図は本
発明による動作原理模式図。第８図は本発明の実
施例のブロツク図で、第９図は第８図で用いられ
る非対称波用の同期検波器の例。第１０図は第８
図で用いられる切換え信号発生器２０の内部の非
対称切換え信号発生部のブロツク図例で、第１１
図は第１０図の各部の波形生成図である。
１……アンテナ、２……基準雑音源、３……サ
ーキユレータスイツチ、４……アイソレータ、５
……局部発振器、６……前置増幅器と周波数変換
器、７……帯域通過フイルター、８……中間周波
増幅器、９……２乗検波器、１０……同期検波
器、１１……積分器、１２……切換え信号用発振
器、１３……スイツチ駆動電源、１４……サーボ
増幅器、１５……パルス変調器、１６……雑音源
駆動電源、１７……バランス用付加雑音源、１８
……結合器、２０……切換え信号発生器、２１…
…パルス幅変調器、２２……基準側トリガーパル
ス発生器、２３……アンドゲート、２４……被測
定側トリガーパルス発生器、２５……ワンシヨツ
トマルチバイブレータ、３１……増幅器、３２…
…反転単位増幅器、３３……アナログスイツチ、
Ｔa……被測定電力、Ｔr……基準電力、Ｔo……
パルス状雑音電力、Ｓ……スイツチ切換え信号、
Ｃ……同期信号、Ｄ……２乗検波器出力信号、
V0……積分器出力電圧、Ｔ……サーボ増幅器出
力電圧、Ｉ……同期検波器出力信号、ｔs……従
来方式のスイツチ切換え時間、ｔa……本発明方
式の被測定側時間、ｔr……本発明方式の基準側
時間、ｔo……パルス状雑音のパルス幅、Ｓa……
サーキユレータスイツチが被測定側にある状態、
Ｓr……サーキユレータスイツチが基準側にある
状態、Ａ……被測定側矩形波、Ｒ……基準側パル
ス、Ｐa……被測定側トリガーパルス、Ｐr……基
準トリガーパルス。
FIG. 1 is an example of a basic block diagram of a conventionally known Deitske radiometer. FIG. 2 is an example of a block diagram of a conventionally known zero-balance radiometer. Third
The figure is a schematic diagram of the operating principle in the case of the pulse width modulation method in Figure 2. FIG. 4, FIG. 5, FIG. 6, and FIG. 7 are schematic diagrams of the operating principle according to the present invention. FIG. 8 is a block diagram of an embodiment of the present invention, and FIG. 9 is an example of a synchronous wave detector for asymmetric waves used in FIG. Figure 10 is the 8th
This is an example of a block diagram of an asymmetric switching signal generator inside the switching signal generator 20 used in the figure.
The figure is a waveform generation diagram of each part in FIG. 10. 1... Antenna, 2... Reference noise source, 3... Circulator switch, 4... Isolator, 5
... Local oscillator, 6 ... Preamplifier and frequency converter, 7 ... Bandpass filter, 8 ... Intermediate frequency amplifier, 9 ... Square law detector, 10 ... Synchronous detector, 11 ... Integrator , 12...Switching signal oscillator, 13...Switch drive power supply, 14...Servo amplifier, 15...Pulse modulator, 16...Noise source drive power supply, 17...Additional noise source for balance, 18
...Coupler, 20...Switching signal generator, 21...
...Pulse width modulator, 22...Reference side trigger pulse generator, 23...And gate, 24...Measurement side trigger pulse generator, 25...One shot multivibrator, 31...Amplifier, 32...
...Inverting unit amplifier, 33...Analog switch,
T a ...Measured power, T r ...Reference power, T o ...
Pulse noise power, S... switch switching signal,
C... synchronization signal, D... square law detector output signal,
V 0 ... Integrator output voltage, T ... Servo amplifier output voltage, I ... Synchronous detector output signal, t s ... Switch switching time of conventional method, t a ... Measured side time of the present invention method, t r ...Reference side time of the method of the present invention, t o ...Pulse width of pulse-like noise, S a ...
When the circulator switch is on the side to be measured,
S r ...Situation in which the circulator switch is on the reference side, A ... Square wave on the side to be measured, R ... Pulse on the reference side, P a ... Trigger pulse on the side to be measured, P r ... Standard trigger pulse.
Claims (1)
有するラジオメータにおいて、切換器を切り換え
る切り換え信号及びそれに同期した切り換え同期
信号を発生する切り換え信号発生器と、切換器か
らの信号を切り換え同期信号で検波する同期検波
器と、同期検波器出力を積分して切り換え信号発
生器を制御する積分器とを有し、被測定電力と被
測定信号に切り換えられている時間の積と、基準
電力と基準信号に切り換えられている時間の積と
が等しくなるように、切り換え時間を制御するこ
とを特徴とする自動バランス型ラジオメータ。1 In a radiometer that has a switching device that switches between the signal under test and the reference signal, there is a switching signal generator that generates a switching signal that switches the switching device and a switching synchronization signal that is synchronized with the switching signal, and a switching signal generator that generates a switching synchronization signal that is synchronized with the switching signal that switches the switching device, and a switching signal that detects the signal from the switching device using the switching synchronization signal. and an integrator that integrates the output of the synchronous detector to control the switching signal generator. An automatically balanced radiometer characterized in that the switching time is controlled so that the product of the switching time is equal to the switching time.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8890781A JPS57204466A (en) | 1981-06-11 | 1981-06-11 | Automatic balance type radiometer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8890781A JPS57204466A (en) | 1981-06-11 | 1981-06-11 | Automatic balance type radiometer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS57204466A JPS57204466A (en) | 1982-12-15 |
| JPS6226710B2 true JPS6226710B2 (en) | 1987-06-10 |
Family
ID=13956010
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8890781A Granted JPS57204466A (en) | 1981-06-11 | 1981-06-11 | Automatic balance type radiometer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS57204466A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0285610U (en) * | 1988-12-22 | 1990-07-05 |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8981794B2 (en) * | 2013-06-25 | 2015-03-17 | Raytheon Company | Loss-less frequency dependent dicke-switched radiometer |
-
1981
- 1981-06-11 JP JP8890781A patent/JPS57204466A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0285610U (en) * | 1988-12-22 | 1990-07-05 |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS57204466A (en) | 1982-12-15 |
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