JPH01202015A - Spectrum display device for input signal - Google Patents

Spectrum display device for input signal

Info

Publication number
JPH01202015A
JPH01202015A JP2644588A JP2644588A JPH01202015A JP H01202015 A JPH01202015 A JP H01202015A JP 2644588 A JP2644588 A JP 2644588A JP 2644588 A JP2644588 A JP 2644588A JP H01202015 A JPH01202015 A JP H01202015A
Authority
JP
Japan
Prior art keywords
center
span
oscillation means
sweep signal
sweeping signal
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.)
Granted
Application number
JP2644588A
Other languages
Japanese (ja)
Other versions
JPH0543209B2 (en
Inventor
Atsushi Hirohata
敦 広畑
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
AIKOMU KK
Icom Inc
Original Assignee
AIKOMU KK
Icom Inc
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by AIKOMU KK, Icom Inc filed Critical AIKOMU KK
Priority to JP2644588A priority Critical patent/JPH01202015A/en
Publication of JPH01202015A publication Critical patent/JPH01202015A/en
Publication of JPH0543209B2 publication Critical patent/JPH0543209B2/ja
Granted legal-status Critical Current

Links

Landscapes

  • Channel Selection Circuits, Automatic Tuning Circuits (AREA)

Abstract

PURPOSE:To always position a set center frequency level on the center of a display screen by providing the title device with a span adjusting means for adjusting a span of a sweeping signal without exerting influence upon a bias voltage of a local oscillation means inserted between a sweeping signal oscillation means and the local oscillation means. CONSTITUTION:The center voltage of a sweeping signal is set up to the same value as the bias voltage of the local oscillation means 3 for determining input frequency at the center position on a display by a sweeping signal center voltage setting means 5 formed in a sweeping signal oscillation means 1 and the span of the sweeping signal is adjusted by the span adjusting means 2 inserted between the sweeping signal oscillation means 1 and the local oscillation means 3 without exerting influence upon the bias voltage. Even when the span or period if the sweeping signal is changed, the center voltage is not changed, and thereby the center frequency of an objective band is always positioned on the center of the display screen without executing specific operation and no display error is generated.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 この発明は受信機の入力信号のスペクトラム表示装置に
関し、特に、入力信号のスペクトラム表示装置に於ける
掃引信号発振手段に関するものである。
DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a spectrum display device for an input signal of a receiver, and more particularly to a sweep signal oscillation means in the spectrum display device for an input signal.

〔従来技術とその課題〕[Conventional technology and its issues]

特定の帯域の電波の状況をスペクトラムとして表示出来
る装置として、例えばバンドスコープやスペクトラムア
ナライザー等がある。その基本構成は第2図に示すよう
に、掃引信号発振手段1から発振された掃引信号でディ
スプレー手段45を制御するとともに、該掃引信号は局
部発振手段3に入力され、ここで同調用の中間周波信号
に変換されてミキサー41に入力される。このミキサー
41にはスペクトラムとして表示されるべき信号、例え
ば受信機の入力信号が入力されており、上記掃引信号で
同調される。このように掃引同調された信号はアンプ4
2、フィルター43、ディテクタ44等を介してディス
プレー45に入力され、スペクトラムとして表示される
Devices that can display the radio wave status of a specific band as a spectrum include, for example, a band scope and a spectrum analyzer. As shown in FIG. 2, its basic configuration is that the display means 45 is controlled by the sweep signal oscillated from the sweep signal oscillation means 1, and the sweep signal is input to the local oscillation means 3, where the tuning intermediate The signal is converted into a frequency signal and input to the mixer 41. A signal to be displayed as a spectrum, such as a receiver input signal, is input to this mixer 41, and is tuned by the above-mentioned sweep signal. The sweep-tuned signal is sent to the amplifier 4.
2. The signal is input to the display 45 via a filter 43, a detector 44, etc., and displayed as a spectrum.

第3図(a)は従来のバンドスコープやスペクトラムア
ナライザーに於ける掃引信号発振手段1と局部発振手段
3及びその間に挿入されるスパン調整手段2の一例を示
すものである。この回路に於いて掃引信号のスパン調整
手段2はDCアンプの前段に設けられた可変抵抗器によ
って構成されている。この構成によって、スパン調整を
行うと掃引信号の中心電圧がスパンの変化にともなって
変化し、その結果ディスプレー上に表示されるスペクト
ラムの中心周波数の位置(通常ディスプレー上の左右の
中心位置に表示される)が変化することとなり、その都
度局部発振器3 (VCOを使用)のバイアスを調整し
なければならず操作が非常に面倒となる。この欠点を解
消しようとすれば、第3図(b)のように、スパンの調
整用の抵抗と局部発振手段3のバイアス調整用の抵抗と
を連動して操作出来るようにする必要があり、構成が複
雑になる欠点がある。
FIG. 3(a) shows an example of a sweep signal oscillation means 1, a local oscillation means 3, and a span adjustment means 2 inserted between them in a conventional bandscope or spectrum analyzer. In this circuit, the sweep signal span adjustment means 2 is constituted by a variable resistor provided before the DC amplifier. With this configuration, when you perform span adjustment, the center voltage of the sweep signal changes as the span changes, resulting in the position of the center frequency of the spectrum displayed on the display (normally displayed at the left and right center positions on the display). ) changes, and the bias of the local oscillator 3 (using a VCO) must be adjusted each time, making the operation extremely troublesome. In order to eliminate this drawback, it is necessary to make it possible to operate the span adjustment resistor and the bias adjustment resistor of the local oscillation means 3 in conjunction, as shown in FIG. 3(b). The disadvantage is that the configuration is complicated.

更に第4図に示すような回路も従来から用いられている
。この構成ではDCアンプの出力の内、交流骨のみがコ
ンデンサーCによって局部発振手段3に入力されるよう
になっているので上記のように、スパン調整にともなっ
て局部発振手段3に入力される掃引信号の中心電圧が変
化するおそれはない。しかしながら、DCアンプ前段の
可変抵抗器を操作してスパン81!1整を行なった場合
、該可変抵抗器の出力の平均電圧の変化(中心電圧の変
化)が−時的に変化するのに伴ってコンデンサーが充放
電し、局部発振手段3のバイアス電圧を一時的に変化さ
せ、結果として中間周波信号の中心電圧、即ち、デンス
プレーに表示される中心周波数のズレを生じることにな
る。また、スパンを大きくした場合には、単位時間の周
波数の変化が大きいため、フィルター等に応答の遅れが
生じ、その結果画面に歪を生じる。この歪を生じさせな
いためには、掃引信号の周期を長くする必要があるが、
この時には掃引信号に歪が発生し表示誤差が生じる。
Furthermore, a circuit as shown in FIG. 4 has also been used in the past. In this configuration, of the output of the DC amplifier, only the AC signal is input to the local oscillation means 3 by the capacitor C, so as mentioned above, the sweep input to the local oscillation means 3 as the span is adjusted. There is no possibility that the center voltage of the signal will change. However, when adjusting the span 81!1 by operating the variable resistor in front of the DC amplifier, the change in the average voltage (change in center voltage) of the output of the variable resistor changes over time. The capacitor is charged and discharged, temporarily changing the bias voltage of the local oscillation means 3, resulting in a shift in the center voltage of the intermediate frequency signal, that is, the center frequency displayed in the density display. Furthermore, when the span is increased, the change in frequency per unit time is large, which causes a delay in the response of filters and the like, resulting in distortion on the screen. In order to prevent this distortion from occurring, it is necessary to lengthen the period of the sweep signal.
At this time, distortion occurs in the sweep signal and a display error occurs.

ところで、近年受信機の受信周波数近傍の電波の状態を
確認するために、バンドスコープやスペクトラムアナラ
イザーを受信機に搭載することがおこなわれている。受
信機に上記のような構成に係るバンドスコープやスペク
トラムアナライザーをそのまま搭載すると、受信機の操
作に加えて、上記スパン調整、周期変更、はもとより中
心周波数の調整等面倒な調整作業が増えてはなはだ面倒
になる欠点がある他、上記表示誤差の問題もそのまま持
ち込まれることになる。
Incidentally, in recent years, in order to check the state of radio waves near the receiving frequency of the receiver, a band scope or a spectrum analyzer has been installed in the receiver. If a band scope or spectrum analyzer with the above configuration is installed in the receiver as is, in addition to operating the receiver, troublesome adjustment work such as the above-mentioned span adjustment, cycle change, and center frequency adjustment will increase. In addition to the disadvantage of being troublesome, the problem of the display error mentioned above is also brought into play.

〔課題を解決するための手段〕[Means to solve the problem]

この発明は上記従来の問題点に鑑みて提案されたもので
あって、掃引信号のスパンや周期を変更しても中心電圧
が変化することがなく、従って目的とする帯域の中心周
波数が、特別な操作をしなくても常に表示画面の中心に
位置するとともに、表示誤差も発生しない入力信号のス
ペクトラム表示装置を提供することを目的とするもので
ある。
This invention was proposed in view of the above-mentioned conventional problems, and the center voltage does not change even if the span or period of the sweep signal is changed. It is an object of the present invention to provide a spectrum display device for an input signal that is always located at the center of the display screen without any manual operation and that does not cause display errors.

この発明は上記従来の事情に鑑みて提案されたものであ
って、以下の手段を採用している。即ち、入力信号の周
波数スペクトラムを表示するスペクトラム表示装置に於
いて、掃引信号の中心電圧を、掃引信号発振手段に設け
られた掃引信号の中心電圧設定手段で、ディスプレー上
の中央位置での入力周波数を決定する局部発振手段のバ
イアス電圧と同じ値に設定するとともに、上記掃引信号
発振手段と局部発振手段の間に挿入されたスパン調整手
段で、上記バイアス電圧に影響を与えることなく掃引信
号のスパンを調整出来るようにしたものである。
This invention has been proposed in view of the above-mentioned conventional circumstances, and employs the following means. That is, in a spectrum display device that displays the frequency spectrum of an input signal, the center voltage of the sweep signal is set to the input frequency at the center position on the display by the center voltage setting means for the sweep signal provided in the sweep signal oscillation means. The span adjustment means inserted between the sweep signal oscillation means and the local oscillation means adjusts the span of the sweep signal without affecting the bias voltage. It is designed so that it can be adjusted.

この構成によって、掃引信号のスパンと周期は該掃引信
号の中心電圧に対して独立性を保ち、スパンあるいは周
期を変化させても中心電圧を変動させることはなくなり
、操作が簡単となる。更に、コンデンサーを使用してい
ないので表示誤差の発生がない。
With this configuration, the span and period of the sweep signal maintain independence with respect to the center voltage of the sweep signal, and even if the span or period is changed, the center voltage does not change, making the operation simple. Furthermore, since no capacitor is used, there is no display error.

〔実施例〕〔Example〕

第1図はこの発明の1実施例を示すブロック回路図であ
る。A/Dコンバーター等の掃引信号発振手段1は、シ
フトレジスターあるいはCPU等(図示しない)の出力
がI10端子11を介して掃引信号に相当する階段波と
なって差動増幅器12の負端子に入力され、また該差動
増幅器12の正端子は下記掃引信号の中心電圧設定手段
5を介して接地された構成となっている。上記掃引信号
の中心電圧設定手段5は半固定抵抗51よりなっており
、該半固定抵抗51の抵抗値は掃引信号の中心電圧に対
応し、且つ該中心電圧は、少なくとも掃引信号発振手段
1の出力端においては、この半固定抵抗51の値のみに
よって決定され、他の要素例えば掃引信号の周期やスパ
ンの値に影響されない。
FIG. 1 is a block circuit diagram showing one embodiment of the present invention. A sweep signal oscillation means 1 such as an A/D converter converts the output of a shift register or a CPU (not shown) into a staircase wave corresponding to a sweep signal via an I10 terminal 11 and inputs it to the negative terminal of a differential amplifier 12. The positive terminal of the differential amplifier 12 is grounded via a center voltage setting means 5 for the sweep signal described below. The center voltage setting means 5 for the sweep signal includes a semi-fixed resistor 51, the resistance value of the semi-fixed resistor 51 corresponds to the center voltage of the sweep signal, and the center voltage is at least the same as that of the sweep signal oscillating means 1. At the output end, it is determined only by the value of this semi-fixed resistor 51, and is not influenced by other factors such as the period and span of the sweep signal.

上記掃引信号発振手段1の出力はスパン調整用のスパン
調整手段2を介して局部発振手段であるVCO31に入
力されるようになっている。■C031には従来と同様
バイアス抵抗32が設けられており、図示しない受信機
等の中間周波数に対応する値に調整されている。上記ス
パン調整手段2は切換抵抗構造になっており、かつ該切
換抵抗を構成する各抵抗がそれぞれ半固定抵抗になって
いる。従って、各半固定抵抗の値を調整しておくことに
よって目的とする表示帯域幅の周波数に対応する掃引信
号のスパンを決定することが出来る。
The output of the sweep signal oscillation means 1 is input to a VCO 31, which is a local oscillation means, via a span adjustment means 2 for span adjustment. (2) C031 is provided with a bias resistor 32 as in the past, and is adjusted to a value corresponding to the intermediate frequency of a receiver, etc. (not shown). The span adjusting means 2 has a switching resistor structure, and each resistor constituting the switching resistor is a semi-fixed resistor. Therefore, by adjusting the value of each semi-fixed resistor, it is possible to determine the span of the sweep signal corresponding to the frequency of the desired display bandwidth.

上記の構成に於いて、掃引信号の中心電圧設定手段であ
る半固定抵抗51は掃引信号の中心電圧が上記局部発振
手段lのバイアス電圧に一致するように調整しておく。
In the above configuration, the semi-fixed resistor 51, which is the center voltage setting means for the sweep signal, is adjusted so that the center voltage of the sweep signal matches the bias voltage of the local oscillation means l.

この作業は例えばスパン調整手段2を操作して抵抗値を
変えたときにディスプレー上の中心周波数が左右に移動
しない値に半固定抵抗51の抵抗値を調整することによ
って行うことができる。逆に、上記のように調整がなさ
れた場合、スパン調整手段2の抵抗を切換て掃引信号の
スパンを変化させても、掃引信号の中心電圧が変動する
ことがなく、従って表示周波数帯域の中心周波数が画面
上の左右に移動することもない。更に、周期の変更はシ
フトレジスターへの入力クロソク周波数の変更、あるい
はCPUで行うことになるが、周期の変更は掃引信号の
中心電圧に影客を与えないので、この場合にも掃引信号
の中心電圧設定手段である半固定抵抗51を調整する必
要はなく、掃引信号の中心電圧に変化を来すことはない
。 上記は、掃引信号発振手段1の入力側にディジタル
信号が使用される場合についての説明であるが、純粋に
アナログ的な掃引信号発振手段であっても、中心電圧の
設定をスパンの設定や周期の設定と独立して行い得る回
路を用いる限り実現可能である。
This work can be done, for example, by adjusting the resistance value of the semi-fixed resistor 51 to a value that does not cause the center frequency on the display to shift left or right when the resistance value is changed by operating the span adjustment means 2. Conversely, when the adjustment is made as described above, even if the span of the sweep signal is changed by switching the resistance of the span adjustment means 2, the center voltage of the sweep signal does not change, and therefore the center voltage of the display frequency band remains unchanged. The frequency does not move left or right on the screen. Furthermore, the period can be changed by changing the input clock frequency to the shift register or by using the CPU, but since changing the period does not affect the center voltage of the sweep signal, the center voltage of the sweep signal can also be changed in this case. There is no need to adjust the semi-fixed resistor 51, which is the voltage setting means, and the center voltage of the sweep signal does not change. The above is an explanation of the case where a digital signal is used on the input side of the sweep signal oscillation means 1, but even with a purely analog sweep signal oscillation means, the center voltage setting can be changed by the span setting or the period. This can be realized as long as a circuit that can perform the process independently of the settings of is used.

〔発明の効果〕〔Effect of the invention〕

以上説明したようにこの発明は、掃引信号の中心電圧の
設定を、該掃引信号の周期やスパンの設定と関わりなく
行うことが出来るようになっているので、掃引信号発振
手段の周期やスパンを変更しても、その中心電圧に変動
を来すことがなく、面倒な調整作業をしないでも設定さ
れた中心周波数が常に表示画面上の中心に位置するよう
になっている。従って、このスペクトラム表示装置を受
信機に適用すると受信操作以外の面倒な操作が少なく、
好都合である。更に、コンデンサーを使用していないの
で、スパン変更直後や、周期を大きくした場合に発生す
る掃引信号の歪による表示誤差も発生しない効果がある
As explained above, in this invention, the center voltage of the sweep signal can be set regardless of the period and span of the sweep signal, so the period and span of the sweep signal oscillation means can be set. Even if the frequency is changed, the center voltage does not change, and the set center frequency is always located at the center of the display screen without any troublesome adjustment work. Therefore, when this spectrum display device is applied to a receiver, there are fewer troublesome operations other than receiving operations.
It's convenient. Furthermore, since no capacitor is used, there is no display error caused by distortion of the sweep signal that occurs immediately after changing the span or when the period is increased.

【図面の簡単な説明】[Brief explanation of the drawing]

第1図はこの発明の1実施例を示すブロック回路図、第
2図はバンドスコープ等の概要を示すブロック図、第3
図は従来のスペクトラムアナライザー等のブロック回路
図、第4図も従来のスペクトラムアナライザー等のブロ
ック回路図の一例である。 図 中、 ■・・・掃引信号発振手段 2・・・スパン調整手段 3・・・局部発振手段 5・・・掃引信号の中心電圧設定手段 =−,’、、V +’、’ 、=− (“k員 第2図
Fig. 1 is a block circuit diagram showing one embodiment of the present invention, Fig. 2 is a block diagram showing an outline of a band scope, etc.
The figure is a block circuit diagram of a conventional spectrum analyzer, etc., and FIG. 4 is also an example of a block circuit diagram of a conventional spectrum analyzer, etc. In the figure, ■...Sweep signal oscillation means 2...Span adjustment means 3...Local oscillation means 5...Sweep signal center voltage setting means =-,',, V +',', =- (“K members Figure 2

Claims (1)

【特許請求の範囲】 入力信号の周波数スペクトラムを表示するスペクトラム
表示装置に於いて、 掃引信号の中心電圧をディスプレー上の中央位置での入
力周波数を決定する局部発振手段のバイアス電圧と同じ
値に設定するための掃引信号発振手段の掃引信号の中心
電圧設定手段 上記掃引信号発振手段と局部発振手段の間に挿入され上
記局部発振手段のバイアス電圧に影響を与えることなく
掃引信号のスパンを調整出来るスパン調整手段 を備えた入力信号のスペクトラム表示装置
[Claims] In a spectrum display device that displays the frequency spectrum of an input signal, the center voltage of the sweep signal is set to the same value as the bias voltage of local oscillation means that determines the input frequency at the center position on the display. means for setting the center voltage of the sweep signal of the sweep signal oscillation means for controlling the sweep signal; a span that is inserted between the sweep signal oscillation means and the local oscillation means and is capable of adjusting the span of the sweep signal without affecting the bias voltage of the local oscillation means; Spectrum display device for input signals with adjustment means
JP2644588A 1988-02-05 1988-02-05 Spectrum display device for input signal Granted JPH01202015A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2644588A JPH01202015A (en) 1988-02-05 1988-02-05 Spectrum display device for input signal

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2644588A JPH01202015A (en) 1988-02-05 1988-02-05 Spectrum display device for input signal

Publications (2)

Publication Number Publication Date
JPH01202015A true JPH01202015A (en) 1989-08-15
JPH0543209B2 JPH0543209B2 (en) 1993-07-01

Family

ID=12193705

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2644588A Granted JPH01202015A (en) 1988-02-05 1988-02-05 Spectrum display device for input signal

Country Status (1)

Country Link
JP (1) JPH01202015A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100766525B1 (en) * 2006-04-12 2007-10-12 엘아이지넥스원 주식회사 Device for controlling span width of spectrum analyzer

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100766525B1 (en) * 2006-04-12 2007-10-12 엘아이지넥스원 주식회사 Device for controlling span width of spectrum analyzer

Also Published As

Publication number Publication date
JPH0543209B2 (en) 1993-07-01

Similar Documents

Publication Publication Date Title
JP2912791B2 (en) High frequency receiver
US5332978A (en) Frequency synthesizer
US7257505B1 (en) System for calibrating integrated circuit filters
US4355413A (en) Phase locked loop circuit
US7471142B2 (en) Filter calibration with cell re-use
US4797637A (en) PLL frequency synthesizer
US5073973A (en) Method and circuitry for automatic control of the frequency for a radio telephone
JPH01202015A (en) Spectrum display device for input signal
JP3756786B2 (en) Filter automatic adjustment circuit
JPS635607A (en) Sound quality controller
JP3715335B2 (en) PLL synthesizer circuit
EP0562794B1 (en) Superheterodyne receiver
JP2003163593A (en) Phase locked loop oscillating apparatus equipped with compensating function for loop gain
US5231390A (en) Selective call receiver with decoder controlled filters
JP2832750B2 (en) Receiver
KR0136944B1 (en) Automatie filterr tuning system using a counter
JPH0697789A (en) Phase shift circuit
JPH0369444B2 (en)
JP2810580B2 (en) PLL detection circuit
JP2832749B2 (en) Receiver
JP2959126B2 (en) Receiver
JPH0637599A (en) Voltage controlled oscillator and electronic equipment
SU1413544A1 (en) Spectrum analyzer
JP2884752B2 (en) Integrated circuit
KR100200717B1 (en) Apparatus and method for controlling switched capacitor bpf for detecting a signal for discriminating a broadcasting state

Legal Events

Date Code Title Description
EXPY Cancellation because of completion of term
FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20080701

Year of fee payment: 15