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2. ɍɫɢɥɢɬɟɥɢ ɦɨɳɧɨɫɬɢ
150
p1
Ⱦɥɹ ɭɫɬɨɣɱɢɜɨɣ ɪɚɛɨɬɵ ɭɫɢɥɢɬɟɥɹ ɛɢɩɨɥɹɪɧɵɣ ɬɪɚɧɡɢɫɬɨɪ ɨɛɵɱɧɨ
ɜɤɥɸɱɚɸɬ ɩɨ ɫɯɟɦɟ ɫ ɨɛɳɢɦ ɷɦɢɬɬɟɪɨɦ (Ɉɗ). Ⱥɤɬɢɜɧɵɟ ɫɜɨɣɫɬɜɚ
ɨɩɪɟɞɟɥɹɸɬɫɹ ɝɟɧɟɪɚɬɨɪɨɦ ɬɨɤɚ ݅
ݑ
ɢ ɤɨɥɥɟɤɬɨɪ-ɷɦɢɬɬɟɪ ݑˍ. Ɂɚɜɢɫɢɦɨɫɬɢ ܫˍ (ܷˍ, ܷ
˄
ɬɨɤɟ, ɩɨɤɚɡɚɧɵ ɧɚ ɪɢɫ. 2.5 (ɜ ɫɬɚɬɢɱɟɫɤɨɦ ɪɟɠɢɦɟ ܫ
ɯɚɪɚɤɬɟɪɢɫɬɢɤɢ ܫ
(ܷ˄) ɩɪɚɤɬɢɱɟɫɤɢ ɧɟ ɡɚɜɢɫɹɬ ɨɬ ܷ
ˍ
ǡɡɚɜɢɫɹɳɟɝɨ ɨɬ ɧɚɩɪɹɠɟɧɢɣ ɛɚɡɚ-ɷɦɢɬɬɟɪ
ˆ
), ɫɧɹɬɵɟ ɧɚ ɩɨɫɬɨɹɧɧɨɦ
˄
). ɉɟɪɟɯɨɞɧɵɟ
ʒൌܫˍ
.
ˍ
ɚ) ɜɵɯɨɞɧɵɟ ȼȺɏ
ܫ
, ɦȺ
ˍ
100
50
0
0.511.52
ܷ
˄
, ȼ
ɛ) ɩɟɪɟɯɨɞɧɚɹ ȼȺɏ
Ɋɢɫ. 2. 5. ɋɬɚɬɢɱɟɫɤɢɟ ɜɨɥɶɬ-ɚɦɩɟɪɧɵɟ ɯɚɪɚɤɬɟɪɢɫɬɢɤɢ ɛɢɩɨɥɹɪɧɨɝɨ ɬɪɚɧɡɢɫɬɨɪɚ
BJT
Ɍɪɚɧɡɢɫɬɨɪ — ɧɟ ɬɨɥɶɤɨ ɚɤɬɢɜɧɵɣ, ɧɨ ɢ ɧɟɥɢɧɟɣɧɵɣ ɷɥɟɦɟɧɬ. ȿɝɨ ɨɫɧɨɜɧɵɟ
ɧɟɥɢɧɟɣɧɵɟ ɫɜɨɣɫɬɜɚ ɨɩɪɟɞɟɥɹɸɬɫɹ ɩɟɪɟɯɨɞɧɨɣ ɯɚɪɚɤɬɟɪɢɫɬɢɤɨɣ:
ɡɚɜɢɫɢɦɨɫɬɶɸ ɜɵɯɨɞɧɨɝɨ ɬɨɤɚ ɨɬ ɜɯɨɞɧɨɝɨ ɧɚɩɪɹɠɟɧɢɹ ܫ
ʒ(ݑ˄
ሻ. ȼ
ɷɤɜɢɜɚɥɟɧɬɧɨɣ ɫɯɟɦɟ ɭɱɬɟɧɵ ɟɳɟ ɬɪɢ ɧɟɥɢɧɟɣɧɵɯ ɷɥɟɦɟɧɬɚ: ɟɦɤɨɫɬɶ
ɷɦɢɬɬɟɪɧɨɝɨ p — n ɩɟɪɟɯɨɞɚ ʠ
ɫɨɩɪɨɬɢɜɥɟɧɢɟ ɪɟɤɨɦɛɢɧɚɰɢɢ ܴ
, ɟɦɤɨɫɬɶ ɤɨɥɥɟɤɬɨɪɧɨɝɨ ɩɟɪɟɯɨɞɚ ʠ
ˠ˒
ɨɬɤɪɵɬɨɝɨ ɷɦɢɬɬɟɪɧɨɝɨ n-p ɩɟɪɟɯɨɞɚ.
˓ˈˍ
ˍ
ɢ
Ʉɪɨɦɟ ɬɨɝɨ, ɜ ɫɯɟɦɭ ɜɤɥɸɱɟɧɵ ɫɨɩɪɨɬɢɜɥɟɧɢɹ ɩɨɬɟɪɶ ɷɥɟɤɬɪɨɦɚɝɧɢɬɧɨɣ
ɷɧɟɪɝɢɢ ɜ ɛɚɡɟ ܴ
ɜɵɜɨɞɨɜ ܮ
, ܮ
˄
, ɷɦɢɬɬɟɪɟ ܴˠɢ ɤɨɥɥɟɤɬɨɪɟ ܴ
˄
.
ˠǡ ܮˍ
, ɚ ɬɚɤɠɟ ɢɧɞɭɤɬɢɜɧɨɫɬɢ
ˍ
31
Ɋɨɦɚɧɸɤ ȼ.Ⱥ. Ⱥɧɚɥɨɝɨɜɵɟ ɭɫɬɪɨɣɫɬɜɚ ɩɪɢɟɦɨɩɟɪɟɞɚɬɱɢɤɨɜ
Ɏɢɡɢɱɟɫɤɢɟ ɩɪɨɰɟɫɫɵ ɜ ɛɢɩɨɥɹɪɧɨɦ ɬɪɚɧɡɢɫɬɨɪɟ ɦɨɠɧɨ ɨɩɢɫɚɬɶ ɩɪɨɫɬɨɣ
ɦɨɞɟɥɶɸ, ɨɫɧɨɜɚɧɧɨɣ ɧɚ ɩɨɧɹɬɢɢ ɞɢɮɮɭɡɢɨɧɧɨɝɨ ɡɚɪɹɞɚ ݍ
, ɬɨ ɟɫɬɶ ɡɚɪɹɞɚ
ˇˋ˗
ɷɥɟɤɬɪɨɧɨɜ, ɩɨɩɚɞɚɸɳɢɯ ɜ ɨɛɥɚɫɬɶ ɛɚɡɵ ɢɡ ɷɦɢɬɬɟɪɧɨɝɨ ɩɟɪɟɯɨɞɚ ɢ
ɩɪɨɯɨɞɹɳɢɯ ɜ ɤɨɥɥɟɤɬɨɪ ɩɨɞ ɞɟɣɫɬɜɢɟɦ ɷɥɟɤɬɪɢɱɟɫɤɨɝɨ ɩɨɥɹ. Ʉɨɝɞɚ
ɷɦɢɬɬɟɪɧɵɣ ɩɟɪɟɯɨɞ ɨɬɤɪɵɬ, ɬɨɤ ɛɚɡɵ ɬɪɚɧɡɢɫɬɨɪɚ ɪɚɜɟɧ ɫɭɦɦɟ ɬɨɤɚ
ɪɟɤɨɦɛɢɧɚɰɢɢ ɢ ɬɨɤɚ ɷɥɟɤɬɪɨɧɨɜ, ɫɨɡɞɚɸɳɢɯ ɞɢɮɮɭɡɢɨɧɧɵɣ ɡɚɪɹɞ. ȼ
ɷɤɜɢɜɚɥɟɧɬɧɨɣ ɫɯɟɦɟ ɬɪɚɧɡɢɫɬɨɪɚ ɷɬɢ ɬɨɤɢ ɭɱɬɟɧɵ ɧɟɥɢɧɟɣɧɵɦ
ɫɨɩɪɨɬɢɜɥɟɧɢɟɦ ܴ
ɨɬɤɪɵɬɨɦ ɷɦɢɬɬɟɪɧɨɦ ɩɟɪɟɯɨɞɟ ܥ
ɷɦɢɬɬɟɪɧɨɝɨ ɩɟɪɟɯɨɞɚ ʠ
ɢ ɧɟɥɢɧɟɣɧɨɣ ɞɢɮɮɭɡɢɨɧɧɨɣ ɟɦɤɨɫɬɶɸ ܥ
˓ˈˍ
= ܥ
ˠ˒
Ȅɷɬɨ ɛɚɪɶɟɪɧɚɹ ɟɦɤɨɫɬɶ ܥ
ˠ˒
ሻǤȼ ɡɚɤɪɵɬɨɦ ɫɨɫɬɨɹɧɢɢ
ˇˋ˗
ˠǤ
ˇˋ˗
(ɩɪɢ
ɗɥɟɦɟɧɬɵ ɷɤɜɢɜɚɥɟɧɬɧɨɣ ɫɯɟɦɵ ɬɪɚɧɡɢɫɬɨɪɚ ɨɩɢɫɵɜɚɸɬɫɹ ɫɥɟɞɭɸɳɢɦɢ
ɜɵɪɚɠɟɧɢɹɦɢ.
1. ȼɨɥɶɬ-ɤɭɥɨɧɧɚɹ ɯɚɪɚɤɬɟɪɢɫɬɢɤɚ ɞɢɮɮɭɡɢɨɧɧɨɣ ɟɦɤɨɫɬɢ ɨɬɤɪɵɬɨɝɨ
ɷɦɢɬɬɟɪɧɨɝɨ ɩɟɪɟɯɨɞɚܥ
ݍ
ˆˇˈ ݍ
— ɡɚɪɹɞ ɷɥɟɤɬɪɨɧɨɜ ɜ ɛɚɡɟ ɩɪɢ ɡɚɤɪɵɬɨɦ ɷɦɢɬɬɟɪɧɨɦ ɩɟɪɟɯɨɞɟ, ߮
ɬɟɩɥɨɜɨɣ ɩɨɬɟɧɰɢɚɥ (ɩɪɢ ɤɨɦɧɚɬɧɨɣ ɬɟɦɩɟɪɚɬɭɪɟ § 0,026 ȼ), ݑ
ˇˋ˗
௨
ˠ˒
ൗ
ఝ
ˇˋ˗
= ݍ(݁
— 1), (2.2)
்
ˠ˒
—
—
ɧɚɩɪɹɠɟɧɢɟ ɧɚ ɷɦɢɬɬɟɪɧɨɦ ɩɟɪɟɯɨɞɟ.
2. ȼɨɥɶɬ — ɚɦɩɟɪɧɚɹ ɯɚɪɚɤɬɟɪɢɫɬɢɤɚ ɝɟɧɟɪɚɬɨɪɚ ɬɨɤɚ
ݍ
ˇˋ˗
݅
ʒ
=
ൗ
, (2.3)
߬
௧
ɝɞɟ ߬
— ɫɪɟɞɧɟɟ ɜɪɟɦɹ ɩɪɨɥɟɬɚ ɷɥɟɤɬɪɨɧɨɜ ɨɛɥɚɫɬɢ ɛɚɡɵ (ɨɬ ɩɥɨɫɤɨɫɬɢ
௧
ɷɦɢɬɬɟɪɧɨɝɨ ɩɟɪɟɯɨɞɚ ɞɨ ɩɥɨɫɤɨɫɬɢ ɤɨɥɥɟɤɬɨɪɧɨɝɨ ɩɟɪɟɯɨɞɚ).
3. Ȼɚɪɶɟɪɧɚɹ ɟɦɤɨɫɬɶ ɡɚɤɪɵɬɨɝɨ ɷɦɢɬɬɟɪɧɨɝɨ ɩɟɪɟɯɨɞɚ ɨɛɵɱɧɨ ɨɩɢɫɵɜɚɟɬɫɹ
ɜɨɥɶɬ-ɮɚɪɚɞɧɨɣ ɯɚɪɚɤɬɟɪɢɫɬɢɤɨɣ
= ʠ
ʠ
ɝɞɟ ܥ
(0) — ɛɚɪɶɟɪɧɚɹ ɟɦɤɨɫɬɶ ɩɟɪɟɯɨɞɚ ɩɪɢ ɧɭɥɟɜɨɦ ɧɚɩɪɹɠɟɧɢɢݑˠ˒, ߮
ˠ
(0)
ˠ
ˠ
ቀ
ఝˍି௨
ˍ
, (2.4)
ቁ
ˠ˒
ఔ
ఝ
ɤɨɧɬɚɤɬɧɚɹ ɪɚɡɧɨɫɬɶ ɩɨɬɟɧɰɢɚɥɨɜ, ࣇ = 0,2…1.
4. Ȼɚɪɶɟɪɧɚɹ ɟɦɤɨɫɬɶ ɡɚɤɪɵɬɨɝɨ ɤɨɥɥɟɤɬɨɪɧɨɝɨ ɩɟɪɟɯɨɞɚ ɨɩɪɟɞɟɥɹɟɬɫɹ
ɜɵɪɚɠɟɧɢɟɦ, ɚɧɚɥɨɝɢɱɧɵɦ (2.4), ɝɞɟ, ɜɦɟɫɬɨ ݑ
ɦɟɠɞɭ ɛɚɡɨɣ ɢ ɤɨɥɥɟɤɬɨɪɨɦ ݑ
.
˄ˍ
5. ȼɨɥɶɬ-ɚɦɩɟɪɧɚɹ ɯɚɪɚɤɬɟɪɢɫɬɢɤɚ ɫɨɩɪɨɬɢɜɥɟɧɢɹ ɪɟɤɨɦɛɢɧɚɰɢɢ ܴ
ݍ
݅
ɝɞɟ ߬
— ɩɨɫɬɨɹɧɧɚɹ ɜɪɟɦɟɧɢ ɪɟɤɨɦɛɢɧɚɰɢɢ ɷɥɟɤɬɪɨɧɨɜ ɜ ɛɚɡɟ n-p-n
˓ˈˍ
˓ˈˍ
ˇˋ˗
=
ൗ , (2.5)
, ɧɭɠɧɨ ɩɨɫɬɚɜɢɬɶ ɧɚɩɪɹɠɟɧɢɟ
ˠ˒ǡ
߬
˓ˈˍ
˓ˈˍ
ɬɪɚɧɡɢɫɬɨɪɚ.
32
ˍ
—
2. ɍɫɢɥɢɬɟɥɢ ɦɨɳɧɨɫɬɢ
ɑɚɫɬɨɬɧɵɟ ɫɜɨɣɫɬɜɚ ɬɪɚɧɡɢɫɬɨɪɚ ɩɪɢɧɹɬɨ ɨɰɟɧɢɜɚɬɶ ɝɪɚɧɢɱɧɨɣ ɱɚɫɬɨɬɨɣ ݂
௧
ɧɚ ɤɨɬɨɪɨɣ ɚɦɩɥɢɬɭɞɚ ɬɨɤɚ ɤɨɥɥɟɤɬɨɪɚ ɬɪɚɧɡɢɫɬɨɪɚ, ɪɚɛɨɬɚɸɳɟɝɨ ɜ ɪɟɠɢɦɟ
ɦɚɥɵɯ ɚɦɩɥɢɬɭɞ ɤɨɥɟɛɚɧɢɣ, ɪɚɜɧɚ ɚɦɩɥɢɬɭɞɟ ɬɨɤɚ ɛɚɡɵ:
ݒ
ˇ
݂
ɝɞɟ ݒ
— ɫɪɟɞɧɹɹ ɞɪɟɣɮɨɜɚɹ ɫɤɨɪɨɫɬɶ ɷɥɟɤɬɪɨɧɨɜ ɜ ɛɚɡɟ, l — ɞɥɢɧɚ ɛɚɡɵ.
ˇ
Ʉɨɷɮɮɢɰɢɟɧɬ ɭɫɢɥɟɧɢɹ ɦɨɳɧɨɫɬɢ ɜɯɨɞɧɵɯ ɤɨɥɟɛɚɧɢɣ ɱɚɫɬɨɬ, ɛɨɥɶɲɢɯ ݂
ൗ
=
௧
, (2.6)
ʹߨ݈
௧
ɜɟɫɶɦɚ ɦɚɥ. ɗɧɟɪɝɟɬɢɱɟɫɤɢɟ ɜɨɡɦɨɠɧɨɫɬɢ ɬɪɚɧɡɢɫɬɨɪɚ ɨɩɪɟɞɟɥɹɸɬɫɹ, ɜ
ɨɫɧɨɜɧɨɦ, ɦɚɤɫɢɦɚɥɶɧɨ ɞɨɩɭɫɬɢɦɨɣ ɦɨɳɧɨɫɬɶɸ, ɩɨɬɪɟɛɥɹɟɦɨɣ ɬɪɚɧɡɢɫɬɨɪɨɦ
ɢɡ ɢɫɬɨɱɧɢɤɚ ɩɢɬɚɧɢɹ ܲ
— ɧɚɩɪɹɠɟɧɢɟ ɢɫɬɨɱɧɢɤɚ ɩɢɬɚɧɢɹ. Ɇɨɳɧɨɫɬɶ ɜɵɯɨɞɧɵɯ ɤɨɥɟɛɚɧɢɣ
˒ˋ˕
= ܫˍܧ
˒ˋ˕
ܲ
˅˞˘
, ɝɞɟ
= ߟܲ
— ɩɨɫɬɨɹɧɧɵɣ ɬɨɤ ɤɨɥɥɟɤɬɨɪɚ,
ˍ
,
ɝɞɟ ߟ — ɄɉȾ ɬɪɚɧɡɢɫɬɨɪɚ.
ɍɫɢɥɢɬɟɥɢ ɧɚ ɛɢɩɨɥɹɪɧɵɯ ɬɪɚɧɡɢɫɬɨɪɚɯ ɭɫɩɟɲɧɨ ɪɚɛɨɬɚɸɬ ɧɚ ɱɚɫɬɨɬɚɯ ɜ
ɟɞɢɧɢɰɵ ȽȽɰ, ɨɫɧɨɜɧɨɟ ɞɨɫɬɨɢɧɫɬɜɨ ȻɌ — ɜɵɫɨɤɚɹ ɬɟɩɥɨɩɪɨɜɨɞɧɨɫɬɶ
ɤɪɟɦɧɢɹ, ɱɬɨ ɨɛɥɟɝɱɚɟɬ ɜɨɡɦɨɠɧɨɫɬɶ ɨɬɜɨɞɚ ɬɟɩɥɚ ɢ ɞɚɟɬ ɜɨɡɦɨɠɧɨɫɬɶ
ɫɨɡɞɚɜɚɬɶ ɬɪɚɧɡɢɫɬɨɪɵ ɜɵɫɨɤɨɣ ɦɨɳɧɨɫɬɢ.
ɇɚɢɛɨɥɟɟ ɭɩɨɬɪɟɛɢɬɟɥɶɧɚɹ ɦɨɞɟɥɶ ɛɢɩɨɥɹɪɧɨɝɨ ɬɪɚɧɡɢɫɬɨɪɚ — ɦɨɞɟɥɶ
Ƚɚɦɟɥɹ-ɉɭɧɚ [5].
2.1.2. ɉɨɥɟɜɨɣ ɬɪɚɧɡɢɫɬɨɪ MESFET
ȼ ɛɨɥɶɲɢɧɫɬɜɟ ɭɫɢɥɢɬɟɥɟɣ ɦɨɳɧɨɫɬɢ ɤɨɥɟɛɚɧɢɣ, ɱɚɫɬɨɬɵ ɤɨɬɨɪɵɯ
ɫɨɫɬɚɜɥɹɸɬ ɞɟɫɹɬɤɢ ɝɢɝɚɝɟɪɰ ɢ ɜɵɲɟ, ɜ ɤɚɱɟɫɬɜɟ ɚɤɬɢɜɧɵɯ ɷɥɟɦɟɧɬɨɜ
ɢɫɩɨɥɶɡɭɸɬ ɩɨɥɟɜɵɟ ɬɪɚɧɡɢɫɬɨɪɵ. ȼ ɩɨɥɟɜɨɦ ɬɪɚɧɡɢɫɬɨɪɟ ɫɭɳɟɫɬɜɭɟɬ ɤɚɧɚɥ ɜ
ɩɨɥɭɩɪɨɜɨɞɧɢɤɟ n ɬɢɩɚ, ɩɨ ɤɨɬɨɪɨɦɭ ɞɜɢɠɟɬɫɹ ɩɨɬɨɤ ɷɥɟɤɬɪɨɧɨɜ ɩɨɞ
ɞɟɣɫɬɜɢɟɦ ɷɥɟɤɬɪɢɱɟɫɤɨɝɨ ɩɨɥɹ, ɫɨɡɞɚɧɧɨɝɨ ɩɨɫɬɨɹɧɧɵɦ ɧɚɩɪɹɠɟɧɢɟɦ,
ɩɪɢɥɨɠɟɧɧɵɦ ɦɟɠɞɭ ɫɬɨɤɨɦ ɢ ɢɫɬɨɤɨɦ. Ɉɬɪɢɰɚɬɟɥɶɧɨɟ ɧɚɩɪɹɠɟɧɢɟ ɦɟɠɞɭ
ɡɚɬɜɨɪɨɦ ɢ ɢɫɬɨɤɨɦ ɜɵɡɵɜɚɟɬ ɩɨɹɜɥɟɧɢɟ ɜ ɤɚɧɚɥɟ ɨɛɥɚɫɬɢ, ɨɛɟɞɧɟɧɧɨɣ
ɷɥɟɤɬɪɨɧɚɦɢ. ɉɟɪɢɨɞɢɱɟɫɤɨɟ ɢɡɦɟɧɟɧɢɟ ɷɬɨɝɨ ɧɚɩɪɹɠɟɧɢɟ ɜɵɡɵɜɚɟɬ
ɢɡɦɟɧɟɧɢɟ ɜɵɫɨɬɵ, ɚ, ɫɥɟɞɨɜɚɬɟɥɶɧɨ, ɢ ɩɥɨɳɚɞɢ ɫɟɱɟɧɢɹ ɤɚɧɚɥɚ, ɱɬɨ ɜ
ɫɨɨɬɜɟɬɫɬɜɢɢ ɫ (2.1) ɩɪɢɜɨɞɢɬ ɤ ɩɟɪɢɨɞɢɱɟɫɤɨɦɭ ɢɡɦɟɧɟɧɢɸ ɬɨɤɚ ɫɬɨɤɚ.
ȼ ɩɪɨɫɬɟɣɲɟɦ ɫɥɭɱɚɟ ɨɛɟɞɧɟɧɧɚɹ ɨɛɥɚɫɬɶ ɨɛɪɚɡɭɟɬɫɹ, ɟɫɥɢ ɦɟɠɞɭ ɤɚɧɚɥɨɦ ɢ
ɡɚɬɜɨɪɨɦ ɜɵɩɨɥɧɟɧ ɩɟɪɟɯɨɞ ɦɟɬɚɥɥ-ɩɨɥɭɩɪɨɜɨɞɧɢɤ ɬɢɩɚ ɛɚɪɶɟɪɚ ɒɨɬɤɢ.
Ɍɪɚɧɡɢɫɬɨɪ
Transistor (MESFET). Ɍɪɚɧɡɢɫɬɨɪ
ɹɱɟɣɤɢ ɩɨɤɚɡɚɧɚ ɧɚ ɪɢɫ. 2.6. ȼ ɭɫɢɥɢɬɟɥɟ ɦɨɳɧɨɫɬɢ ɬɪɚɧɡɢɫɬɨɪ ɨɛɵɱɧɨ
ɜɤɥɸɱɚɸɬ ɩɨ ɫɯɟɦɟ ɫ ɨɛɳɢɦ ɢɫɬɨɤɨɦ (Ɉɂ).
ɫ ɛɚɪɶɟɪɨɦ ɒɨɬɤɢ ɧɨɫɢɬ ɧɚɡɜɚɧɢɟ Metal Semiconducter Field Effect
MESFET ɢɡɝɨɬɨɜɥɹɸɬ ɢɡ GaAs, ɫɬɪɭɤɬɭɪɚ ɟɝɨ
,
,
33
Ɋɨɦɚɧɸɤ ȼ.Ⱥ. Ⱥɧɚɥɨɝɨɜɵɟ ɭɫɬɪɨɣɫɬɜɚ ɩɪɢɟɦɨɩɟɪɟɞɚɬɱɢɤɨɜ
r
r
ɂ
Ɋɢɫ. 2.6. ɋɬɪɭɤɬɭɪɚ ɹɱɟɣɤɢ ɩɨɥɟɜɨɝɨ ɬɪɚɧɡɢɫɬɨɪɚ MESFET.
ɉɪɨɫɬɟɣɲɟɣ ɦɨɞɟɥɶɸ ɬɪɚɧɡɢɫɬɨɪɚ ɫɬɪɭɤɬɭɪɵ MESFET ɹɜɥɹɟɬɫɹ
ɷɤɜɢɜɚɥɟɧɬɧɚɹ ɫɯɟɦɚ ɧɚ ɷɥɟɦɟɧɬɚɯ ɫ ɫɨɫɪɟɞɨɬɨɱɟɧɧɵɦɢ ɩɚɪɚɦɟɬɪɚɦɢ —
ɪɢɫ. 2.7.
Ɂ
ɡ
C
R
Ɋɢɫ. 2.7. ɗɤɜɢɜɚɥɟɧɬɧɚɹ ɫɯɟɦɚ ɩɨɥɟɜɨɝɨ ɬɪɚɧɡɢɫɬɨɪɚ ɫ ɛɚɪɶɟɪɨɦ ɒɨɬɤɢ.
Ⱥɤɬɢɜɧɵɟ ɫɜɨɣɫɬɜɚ ɬɪɚɧɡɢɫɬɨɪɚ ɩɪɟɞɫɬɚɜɥɟɧɵ ɝɟɧɟɪɚɬɨɪɨɦ ɬɨɤɚ ݅
ɡɚɜɢɫɹɳɢɦ ɨɬ ɧɚɩɪɹɠɟɧɢɹ ɡɚɬɜɨɪ-ɢɫɬɨɤ ݑ
C
ɡ-ɫ
ɡ-ɢ
ɤ
r
ɢ
ɫ
i
ɝ
ɋ
ˆ
ɢ ɧɚɩɪɹɠɟɧɢɹ ɫɬɨɤ-ɢɫɬɨɤ ݑ
ˊ
. ɗɬɚ
˔˕
ɡɚɜɢɫɢɦɨɫɬɶ ɨɞɢɧɚɤɨɜɚ ɞɥɹ ɩɨɫɬɨɹɧɧɨɝɨ ɢ ɩɟɪɟɦɟɧɧɨɝɨ ɬɨɤɨɜ ɢ ɨɛɪɚɡɭɟɬ
ɫɟɦɟɣɫɬɜɨ ɜɵɯɨɞɧɵɯ ɢ ɩɟɪɟɯɨɞɧɵɯ ɜɨɥɶɬ-ɚɦɩɟɪɧɵɯ ɯɚɪɚɤɬɟɪɢɫɬɢɤ ݅
(ݑ˔˕, ݑ
ˆ
).
ˊ
ɇɚ ɪɢɫ. 2.8 ɩɨɤɚɡɚɧɵ ɜɨɥɶɬ-ɚɦɩɟɪɧɵɟ ɯɚɪɚɤɬɟɪɢɫɬɢɤɢ ɬɪɚɧɡɢɫɬɨɪɚ, ɫɧɹɬɵɟ ɧɚ
ɩɨɫɬɨɹɧɧɨɦ ɬɨɤɟ.
,
34
2. ɍɫɢɥɢɬɟɥɢ ɦɨɳɧɨɫɬɢ
ɚ — ɜɵɯɨɞɧɵɟ ȼȺɏ
ɛ — ɩɟɪɟɯɨɞɧɵɟ ȼȺɏ
Ɋɢɫ. 2.8. ɋɬɚɬɢɱɟɫɤɢɟ ɜɨɥɶɬ-ɚɦɩɟɪɧɵɟ ɯɚɪɚɤɬɟɪɢɫɬɢɤɢ ɩɨɥɟɜɨɝɨ ɬɪɚɧɡɢɫɬɨɪɚ ɫ
ɛɚɪɶɟɪɨɦ ɒɨɬɤɢ
ȼ ɷɤɜɢɜɚɥɟɧɬɧɨɣ ɫɯɟɦɟ ɭɱɬɟɧɵ ɟɦɤɨɫɬɢ ɡɚɬɜɨɪ — ɢɫɬɨɤ ܥ
ɫɬɨɤ ʠ
, ɨɛɪɚɡɨɜɚɧɧɵɟ ɩɨɥɨɠɢɬɟɥɶɧɵɦ ɡɚɪɹɞɨɦ ɨɛɥɚɫɬɢ ɤɚɧɚɥɚ, ɨɛɟɞɧɟɧɧɨɣ
ˊି˔
ɢ ɡɚɬɜɨɪ —
ˊିˋ
ɷɥɟɤɬɪɨɧɚɦɢ, ɢ ɨɬɪɢɰɚɬɟɥɶɧɵɦ ɡɚɪɹɞɨɦ ɫɤɨɩɥɟɧɢɹ ɷɥɟɤɬɪɨɧɨɜ ɜ ɦɟɬɚɥɥɟ
ɡɚɬɜɨɪɚ. ɗɬɢ ɟɦɤɨɫɬɢ ɧɟɥɢɧɟɣɧɵ ɢ ɨɩɢɫɵɜɚɸɬɫɹ ɜɨɥɶɬ-ɮɚɪɚɞɧɵɦɢ
35
Ɋɨɦɚɧɸɤ ȼ.Ⱥ. Ⱥɧɚɥɨɝɨɜɵɟ ɭɫɬɪɨɣɫɬɜɚ ɩɪɢɟɦɨɩɟɪɟɞɚɬɱɢɤɨɜ
ɯɚɪɚɤɬɟɪɢɫɬɢɤɚɦɢ ɡɚɤɪɵɬɨɝɨ ɛɚɪɶɟɪɚ ɒɨɬɤɢ. Ɉɫɬɚɥɶɧɵɟ ɷɥɟɦɟɧɬɵ ɫɯɟɦɵ
ɜɜɟɞɟɧɵ ɞɥɹ ɭɱɟɬɚ ɩɨɬɟɪɶ ɦɨɳɧɨɫɬɢ ɜ ɡɚɬɜɨɪɟ ݎ
, ɤɚɧɚɥɟ ݎˍ, ɢɫɬɨɤɟ ݎˋɢ ɫɬɨɤɟ ݎ
ˊ
Ɋɚɛɨɱɟɣ ɨɛɥɚɫɬɶɸ ɉɌɒ ɹɜɥɹɸɬɫɹ ɞɢɚɩɚɡɨɧ ɨɬɪɢɰɚɬɟɥɶɧɵɯ ɧɚɩɪɹɠɟɧɢɣ ɧɚ
ɡɚɬɜɨɪɟ. ɉɪɢ ɩɨɥɨɠɢɬɟɥɶɧɨɦ ɧɚɩɪɹɠɟɧɢɢ ɧɚ ɡɚɬɜɨɪɟ, ɛɨɥɶɲɢɦ ɩɨɬɟɧɰɢɚɥɚ
ɛɚɪɶɟɪɚ ɒɨɬɤɢ, ɛɚɪɶɟɪ ɨɬɤɪɵɜɚɟɬɫɹ, ɷɬɨ ɜɵɡɵɜɚɟɬ ɭɜɟɥɢɱɟɧɢɟ ɬɨɤɚ ɡɚɬɜɨɪɚ,
ɱɬɨ ɦɨɠɟɬ ɩɪɢɜɟɫɬɢ ɤ ɫɝɨɪɚɧɢɸ ɬɪɚɧɡɢɫɬɨɪɚ. ɉɪɢɦɟɧɟɧɢɟ ɜ ɭɫɢɥɢɬɟɥɹɯ
ɩɨɥɟɜɵɯ ɬɪɚɧɡɢɫɬɨɪɨɜ ɫ ɛɚɪɶɟɪɨɦ ɒɨɬɤɢ, ɜɦɟɫɬɨ ɛɢɩɨɥɹɪɧɵɯ n-p-n ɬɢɩɚ,
ɩɨɡɜɨɥɢɥɨ ɭɜɟɥɢɱɢɬɶ ɱɚɫɬɨɬɵ ɭɫɢɥɢɜɚɟɦɵɯ ɤɨɥɟɛɚɧɢɣ ɞɨ ɞɟɫɹɬɤɨɜ ȽȽɰ.
Ɋɚɡɪɚɛɨɬɚɧɵ ɤɨɦɩɶɸɬɟɪɧɵɟ ɦɨɞɟɥɢ ɬɪɚɧɡɢɫɬɨɪɚ ɫɬɪɭɤɬɭɪɵ MESFET, ɜ
ɤɨɬɨɪɵɯ ɩɪɟɞɥɨɠɟɧɵ ɦɚɬɟɦɚɬɢɱɟɫɤɢɟ ɫɨɨɬɧɨɲɟɧɢɹ ɞɥɹ ɪɚɫɱɟɬɚ ɧɟɥɢɧɟɣɧɵɯ
ɯɚɪɚɤɬɟɪɢɫɬɢɤ ɷɥɟɦɟɧɬɨɜ ɷɤɜɢɜɚɥɟɧɬɧɨɣ ɫɯɟɦɵ: Angelov [6], Tom [7].
2.2. ȼɧɟɲɧɢɟ ɰɟɩɢ ɚɤɬɢɜɧɨɝɨ ɷɥɟɦɟɧɬɚ ɜ ɭɫɢɥɢɬɟɥɟ
2.2.1. ɐɟɩɢ ɩɢɬɚɧɢɹ ɢ ɫɦɟɳɟɧɢɹ
ɇɚɢɛɨɥɟɟ ɪɚɫɩɪɨɫɬɪɚɧɟɧɧɵɟ ɫɯɟɦɵ ɜɤɥɸɱɟɧɢɹ ɬɪɚɧɡɢɫɬɨɪɚ ɜ ɰɟɩɶ
ɩɨɫɬɨɹɧɧɨɝɨ ɬɨɤɚ: ɩɨɥɟɜɨɝɨ — ɫ ɨɛɳɢɦ ɢɫɬɨɤɨɦ, ɛɢɩɨɥɹɪɧɨɝɨ — ɫ ɨɛɳɢɦ
ɷɦɢɬɬɟɪɨɦ.
ɋɯɟɦɵ ɜɤɥɸɱɟɧɢɹ ɬɪɚɧɡɢɫɬɨɪɨɜ ɩɨ ɩɨɫɬɨɹɧɧɨɦɭ ɬɨɤɭ ɩɨɤɚɡɚɧɵ ɧɚ ɪɢɫ. 2.9.
.
ɚ) ɛ)
Ɋɢɫ. 2.9. ɉɢɬɚɧɢɟ ɢ ɫɦɟɳɟɧɢɟ ɬɪɚɧɡɢɫɬɨɪɨɜ
ɚ) ɩɨɥɟɜɨɣ ɬɪɚɧɡɢɫɬɨɪ ɫ ɛɚɪɶɟɪɨɦ ɒɨɬɤɢ, ɛ) ɛɢɩɨɥɹɪɧɵɣ n-p-n ɬɪɚɧɡɢɫɬɨɪ
ɇɚɩɪɹɠɟɧɢɟ ɩɢɬɚɧɢɹ ɫɥɭɠɢɬ ɢɫɬɨɱɧɢɤɨɦ ɷɧɟɪɝɢɢ ɞɥɹ ɭɜɟɥɢɱɟɧɢɹ
ɦɨɳɧɨɫɬɢ ɜɯɨɞɧɵɯ ɤɨɥɟɛɚɧɢɣ, ɚ ɧɚɩɪɹɠɟɧɢɟ ɫɦɟɳɟɧɢɹ ɭɫɬɚɧɚɜɥɢɜɚɟɬ
ɨɩɬɢɦɚɥɶɧɭɸ ɬɨɱɤɭ ɧɚ ɩɟɪɟɯɨɞɧɨɣ ɯɚɪɚɤɬɟɪɢɫɬɢɤɟ ɬɪɚɧɡɢɫɬɨɪɚ. Ʉɚɤ ɜɢɞɧɨ ɢɡ
ɪɢɫ. 2.9, ɫɭɳɟɫɬɜɭɟɬ ɪɚɡɧɢɰɚ ɜ ɩɨɥɹɪɧɨɫɬɢ ɩɨɫɬɨɹɧɧɨɝɨ ɧɚɩɪɹɠɟɧɢɹ ɫɦɟɳɟɧɢɹ
ɜ ɩɨɥɟɜɵɯ ɢ ɛɢɩɨɥɹɪɧɵɯ ɬɪɚɧɡɢɫɬɨɪɚɯ.
Ⱦɥɹ ɧɟɡɚɜɢɫɢɦɨɝɨ ɫɭɳɟɫɬɜɨɜɚɧɢɹ ɰɟɩɟɣ ɩɨɫɬɨɹɧɧɨɝɨ ɢ ɩɟɪɟɦɟɧɧɨɝɨ ɬɨɤɨɜ
ɩɪɢɦɟɧɹɸɬ ɟɦɤɨɫɬɢ C ɢ ɢɧɞɭɤɬɢɜɧɨɫɬɢ L, ɭɱɢɬɵɜɚɹ ɢɯ ɫɨɩɪɨɬɢɜɥɟɧɢɹ
36
2. ɍɫɢɥɢɬɟɥɢ ɦɨɳɧɨɫɬɢ
ͳ
ܺ
= —
, ܺ= + ߱ܮ,
ൗ
߱ܥ
ɝɞɟ ߱ൌʹߨ݂ — ɤɪɭɝɨɜɚɹ ɱɚɫɬɨɬɚ ɤɨɥɟɛɚɧɢɣ. ɍɤɚɡɚɧɧɵɟ ɷɥɟɦɟɧɬɵ ɰɟɩɢ
ɛɵɜɚɸɬ ɪɚɡɞɟɥɢɬɟɥɶɧɵɟ ɢ ɛɥɨɤɢɪɨɜɨɱɧɵɟ.
Ɋɚɡɞɟɥɢɬɟɥɶɧɵɟ ɟɦɤɨɫɬɢ ɜɤɥɸɱɚɸɬ ɩɨɫɥɟɞɨɜɚɬɟɥɶɧɨ ɜ ɬɪɚɤɬ ɩɪɨɬɟɤɚɧɢɹ
ɩɟɪɟɦɟɧɧɨɝɨ ɬɨɤɚ. Ȼɥɨɤɢɪɨɜɨɱɧɵɟ ɟɦɤɨɫɬɢ ɭɫɬɚɧɚɜɥɢɜɚɸɬ ɩɚɪɚɥɥɟɥɶɧɨ
ɷɥɟɦɟɧɬɭ ɰɟɩɢ, ɜ ɤɨɬɨɪɵɣ ɧɟɠɟɥɚɬɟɥɶɧɨ ɩɨɩɚɞɚɧɢɟ ɩɟɪɟɦɟɧɧɨɝɨ ɬɨɤɚ.
Ȼɥɨɤɢɪɨɜɨɱɧɵɟ ɢɧɞɭɤɬɢɜɧɨɫɬɢ ɜɤɥɸɱɚɸɬ ɩɨɫɥɟɞɨɜɚɬɟɥɶɧɨ ɫ ɢɫɬɨɱɧɢɤɚɦɢ
ɩɨɫɬɨɹɧɧɨɝɨ ɬɨɤɚ, ɨɛɪɚɡɭɹ ɩɚɪɚɥɥɟɥɶɧɵɟ ɤɨɧɬɭɪɚ ɞɥɹ ɩɟɪɟɦɟɧɧɨɝɨ ɢ
ɩɨɫɬɨɹɧɧɨɝɨ ɬɨɤɨɜ ɬɪɚɧɡɢɫɬɨɪɚ.
ɋɯɟɦɚ ɬɪɚɧɡɢɫɬɨɪɧɨɝɨ ɭɫɢɥɢɬɟɥɹ ɦɨɳɧɨɫɬɢ ɩɪɟɞɫɬɚɜɥɟɧɚ ɧɚ ɪɢɫ. 2.10, ɨɧɚ
ɫɨɞɟɪɠɢɬ ɜɯɨɞɧɭɸ ɢ ɜɵɯɨɞɧɭɸ ɫɨɝɥɚɫɭɸɳɢɟ ɰɟɩɢ, ɪɚɡɞɟɥɢɬɟɥɶɧɵɟ
ɟɦɤɨɫɬɢܥ
ɛɥɨɤɢɪɭɸɳɢɟ ɢɫɬɨɱɧɢɤɢ ɫɦɟɳɟɧɢɹ ܧ
ܧ
, ɛɥɨɤɢɪɨɜɨɱɧɵɟ ɟɦɤɨɫɬɢ ܥଵȄܥଷ ɢ ɛɥɨɤɢɪɨɜɨɱɧɚɹ ɢɧɞɭɤɬɢɜɧɨɫɬɶ ܮ
˔ˏ
ɨɛɪɚɡɭɸɬ ɰɟɩɶ ɫɦɟɳɟɧɢɹ, ɚ ɢɫɬɨɱɧɢɤ ܧ
ɟɦɤɨɫɬɹɦɢ ܥ
, ɛɥɨɤɢɪɨɜɨɱɧɵɟ ɢɧɞɭɤɬɢɜɧɨɫɬɢ ܮ˄ˎ ɢ ɟɦɤɨɫɬɢ ʠଵȄʠ
˓
Ȅܥ
ସ
ɢ ɩɢɬɚɧɢɹ ܧ
˔ˏ
ɫɨɜɦɟɫɬɧɨ ɫ ɛɥɨɤɢɪɨɜɨɱɧɵɦɢ
˒ˋ˕
ɢ ɛɥɨɤɢɪɨɜɨɱɧɨɣ ɢɧɞɭɤɬɢɜɧɨɫɬɶɸ — ɰɟɩɶ ɩɢɬɚɧɢɹ.
. ɂɫɬɨɱɧɢɤ ɧɚɩɪɹɠɟɧɢɹ
˒ˋ˕
˄ˎ
ȼɚɠɧɨ, ɱɬɨɛɵ ɜ ɰɟɩɢ ɫɦɟɳɟɧɢɹ ɢ ɩɢɬɚɧɢɹ ɧɟ ɩɨɩɚɞɚɥ ɩɟɪɟɦɟɧɧɵɣ ɬɨɤ
ɭɫɢɥɢɜɚɟɦɵɯ ɢ ɭɫɢɥɟɧɧɵɯ ɤɨɥɟɛɚɧɢɣ. ɋ ɷɬɨɣ ɰɟɥɶɸ ɛɥɨɤɢɪɨɜɨɱɧɵɟ
ɢɧɞɭɤɬɢɜɧɨɫɬɢ ɞɨɥɠɧɵ ɛɵɬɶ ɞɨɫɬɚɬɨɱɧɨ ɛɨɥɶɲɢɦɢ. ɋɨɩɪɨɬɢɜɥɟɧɢɟ
ɛɥɨɤɢɪɨɜɨɱɧɨɣ ɢɧɞɭɤɬɢɜɧɨɫɬɢ ɜɨ ɜɯɨɞɧɨɣ ɱɚɫɬɢ ɭɫɢɥɢɬɟɥɹ ɪɚɫɫɱɢɬɵɜɚɟɬɫɹ ɢɡ
ɫɨɨɬɧɨɲɟɧɢɹ ߱ܮ
ȁ — ɦɨɞɭɥɶ ɜɯɨɞɧɨɝɨ ɫɨɩɪɨɬɢɜɥɟɧɢɹ ɬɪɚɧɡɢɫɬɨɪɚ. Ⱥɧɚɥɨɝɢɱɧɨ,
|ܼ
˅˘
ب |ܼ˅˘ȁ, ɝɞɟ ߱ — ɤɪɭɝɨɜɚɹ ɱɚɫɬɨɬɚ ɜɯɨɞɧɵɯ ɤɨɥɟɛɚɧɢɣ,
˄ˎ
ɫɨɩɪɨɬɢɜɥɟɧɢɟ ɜɵɯɨɞɧɨɣ ɛɥɨɤɢɪɨɜɨɱɧɨɣ ɢɧɞɭɤɬɢɜɧɨɫɬɢ ɞɨɥɠɧɨ ɛɵɬɶ ɦɧɨɝɨ
ɛɨɥɶɲɟ ɦɨɞɭɥɹ ɜɯɨɞɧɨɝɨ ɫɨɩɪɨɬɢɜɥɟɧɢɹ ɜɵɯɨɞɧɨɣ ɫɨɝɥɚɫɭɸɳɟɣ ɰɟɩɢ.
ȼ ɪɚɞɢɨɬɟɯɧɢɱɟɫɤɢɯ ɭɫɬɪɨɣɫɬɜɚɯ ɢɫɬɨɱɧɢɤɢ ܧ
˔ˏ
ɢ ܧ
ɫɥɭɠɚɬ ɞɥɹ ɫɦɟɳɟɧɢɹ
˒ˋ˕
ɢ ɩɢɬɚɧɢɹ ɬɪɚɧɡɢɫɬɨɪɨɜ ɪɚɡɧɵɯ ɤɚɫɤɚɞɨɜ ɭɫɢɥɢɬɟɥɟɣ ɢ ɪɚɡɧɵɯ ɭɫɬɪɨɣɫɬɜ. Ⱦɥɹ
ɭɫɬɨɣɱɢɜɨɣ ɪɚɛɨɬɵ ɪɚɞɢɨɭɫɬɪɨɣɫɬɜ ɫɥɟɞɭɟɬ ɢɫɤɥɸɱɢɬɶ ɜɨɡɦɨɠɧɨɫɬɶ
ɩɨɩɚɞɚɧɢɹ ɩɟɪɟɦɟɧɧɨɝɨ ɬɨɤɚ ɜ ɢɫɬɨɱɧɢɤɢ ɩɨɫɬɨɹɧɧɨɝɨ ɧɚɩɪɹɠɟɧɢɹ. Ⱦɥɹ ɷɬɨɝɨ
ɢɫɬɨɱɧɢɤɢ ɲɭɧɬɢɪɭɸɬ ɟɦɤɨɫɬɹɦɢ ɬɚɤɢɯ ɧɨɦɢɧɚɥɨɜ, ɩɪɢ ɤɨɬɨɪɵɯ
ɫɨɩɪɨɬɢɜɥɟɧɢɹ ɟɦɤɨɫɬɟɣ ɜɟɫɶɦɚ ɦɚɥɵ ɜɨ ɜɫɟɦ ɞɢɚɩɚɡɨɧɟ ɱɚɫɬɨɬ ɭɫɢɥɢɬɟɥɹ
ͳ
(
ൎ 1 Ɉɦ). ȼ ɲɢɪɨɤɨɩɨɥɨɫɧɵɯ ɭɫɢɥɢɬɟɥɹɯ ɜɤɥɸɱɚɸɬ ɩɚɪɚɥɥɟɥɶɧɨ
ൗ
߱ʠ
ɧɟɫɤɨɥɶɤɨ ɟɦɤɨɫɬɟɣ ɫ ɬɟɦ, ɱɬɨɛɵ ɦɚɥɨɟ ɫɨɩɪɨɬɢɜɥɟɧɢɟ ɜɵɞɟɪɠɢɜɚɥɨɫɶ ɧɚ ɜɫɟɯ
ɱɚɫɬɨɬɚɯ ɞɢɚɩɚɡɨɧɚ — ɪɢɫ. 2.10.
(ɇɚɩɪɢɦɟɪ, ɜ ɭɫɢɥɢɬɟɥɹɯ ɝɢɝɚɝɟɪɰɨɜɨɝɨ ɞɢɚɩɚɡɨɧɚ ɩɚɪɚɥɥɟɥɶɧɨ ɜɤɥɸɱɚɸɬ
ɟɦɤɨɫɬɢ 100 ɩɎ, 0,01 ɦɤɎ, 10 ɦɤɎ).
Ɉɛɴɹɫɧɹɟɬɫɹ ɷɬɨ ɬɟɦ, ɱɬɨ ɟɦɤɨɫɬɢ ɛɨɥɶɲɨɝɨ ɧɨɦɢɧɚɥɚ, ɢɦɟɸɳɢɟ ɦɚɥɨɟ
ɫɨɩɪɨɬɢɜɥɟɧɢɟ
ɧɚ ɧɢɡɤɢɯ ɱɚɫɬɨɬɚɯ, ɧɚ ɛɨɥɟɟ ɜɵɫɨɤɢɯ ɱɚɫɬɨɬɚɯ ɦɨɝɭɬ
ɩɪɟɞɫɬɚɜɥɹɬɶ ɫɨɛɨɣ ɭɠɟ ɢɧɞɭɤɬɢɜɧɨɫɬɢ ɢ ɬɟɪɹɸɬ ɛɥɨɤɢɪɨɜɨɱɧɵɟ ɫɜɨɣɫɬɜɚ.
,
37
Ɋɨɦɚɧɸɤ ȼ.Ⱥ. Ⱥɧɚɥɨɝɨɜɵɟ ɭɫɬɪɨɣɫɬɜɚ ɩɪɢɟɦɨɩɟɪɟɞɚɬɱɢɤɨɜ
Ɋɢɫ. 2.10. Ɏɪɚɝɦɟɧɬ ɫɯɟɦɵ ɭɫɢɥɢɬɟɥɹ ɦɨɳɧɨɫɬɢ ɧɚ ɩɨɥɟɜɨɦ ɬɪɚɧɡɢɫɬɨɪɟ.
Ɋɚɡɞɟɥɢɬɟɥɶɧɵɟ ɟɦɤɨɫɬɢ ɞɨɥɠɧɵ ɢɦɟɬɶ ɦɚɥɵɟ ɫɨɩɪɨɬɢɜɥɟɧɢɹ
ͳ
, ɩɨ
ൗ
߱ʠ
ɫɪɚɜɧɟɧɢɸ ɫ ɫɨɩɪɨɬɢɜɥɟɧɢɹɦɢ ɩɨɫɥɟɞɭɸɳɢɯ ɷɥɟɦɟɧɬɨɜ ɰɟɩɢ. Ɍɚɤ,
ͳ
ɫɨɩɪɨɬɢɜɥɟɧɢɟ ɜɯɨɞɧɨɣ ɪɚɡɞɟɥɢɬɟɥɶɧɨɣ ɟɦɤɨɫɬɢ
ɞɨɥɠɧɨ ɛɵɬɶ
ൗ
߱ܥ
˓
ɫɭɳɟɫɬɜɟɧɧɨ ɦɟɧɶɲɟ ɦɨɞɭɥɹ ɜɯɨɞɧɨɝɨ ɢɦɩɟɞɚɧɫɚ ɬɪɚɧɡɢɫɬɨɪɚ, ɫɨɩɪɨɬɢɜɥɟɧɢɟ
ɪɚɡɞɟɥɢɬɟɥɶɧɨɣ ɟɦɤɨɫɬɢ ɧɚ ɜɵɯɨɞɟ ا ɦɨɞɭɥɹ ɜɯɨɞɧɨɝɨ ɢɦɩɟɞɚɧɫɚ ɜɵɯɨɞɧɨɣ
ɫɨɝɥɚɫɭɸɳɟɣ ɰɟɩɢ.
2.2.2. ɋɨɝɥɚɫɭɸɳɢɟ ɰɟɩɢ ɭɫɢɥɢɬɟɥɟɣ ɦɨɳɧɨɫɬɢ
ȼɯɨɞɧɚɹ ɫɨɝɥɚɫɭɸɳɚɹ ɰɟɩɶ ɩɪɟɨɛɪɚɡɭɟɬ ɜɯɨɞɧɨɣ ɢɦɩɟɞɚɧɫ ɬɪɚɧɡɢɫɬɨɪɚ ɜ
ɫɨɩɪɨɬɢɜɥɟɧɢɟ, ɪɚɜɧɨɟ ɜɧɭɬɪɟɧɧɟɦɭ ɫɨɩɪɨɬɢɜɥɟɧɢɸ ɢɫɬɨɱɧɢɤɚ ɤɨɥɟɛɚɧɢɣ.
ȼɯɨɞɧɨɣ ɢɦɩɟɞɚɧɫ ɬɪɚɧɡɢɫɬɨɪɚ ɨɩɪɟɞɟɥɹɟɬɫɹ ɫɥɟɞɭɸɳɢɦ ɨɛɪɚɡɨɦ
ࢁ
ܼ
, ࡵ
ɝɞɟ ࢁ
˅˘
— ɤɨɦɩɥɟɤɫɧɵɟ ɚɦɩɥɢɬɭɞɵ ɩɟɪɜɨɣ ɝɚɪɦɨɧɢɤɢ ɜɯɨɞɧɵɯ
˅˘ଵ
ɧɚɩɪɹɠɟɧɢɹ ɢ ɬɨɤɚ ɬɪɚɧɡɢɫɬɨɪɚ.
ȼ ɪɟɡɭɥɶɬɚɬɟ ɩɪɟɨɛɪɚɡɨɜɚɧɢɹ ɢɫɬɨɱɧɢɤ ɤɨɥɟɛɚɧɢɣ ɨɤɚɡɵɜɚɟɬɫɹ
ɧɚɝɪɭɠɟɧɧɵɦ ɧɚ ɜɯɨɞɧɨɟ ɫɨɩɪɨɬɢɜɥɟɧɢɟ ɜɯɨɞɧɨɣ ɫɨɝɥɚɫɭɸɳɟɣ ɰɟɩɢ
ܴ
Ⱦɥɹ ɧɚɝɪɭɡɤɢ ɬɪɚɧɡɢɫɬɨɪ ɦɨɠɧɨ ɩɪɟɞɫɬɚɜɢɬɶ ɜɵɯɨɞɧɵɦ ɢɦɩɟɞɚɧɫɨɦ ܼ
ࢁ
˅˞˘
ൗ =ܴ
ࡵ
˅˞˘
˅˞˘
+ ݆ܺ
˅˞˘
ǡɝɞɟ ࢁ
ɝɚɪɦɨɧɢɤɢ ɜɵɯɨɞɧɨɝɨ ɧɚɩɪɹɠɟɧɢɹ ɢ ɬɨɤɚ ɬɪɚɧɡɢɫɬɨɪɚ, ܴ
ɨɩɪɟɞɟɥɹɟɬɫɹ, ɜ ɨɫɧɨɜɧɨɦ, ɜɧɭɬɪɟɧɧɟɣ ɟɦɤɨɫɬɶɸ ɢ ɢɧɞɭɤɬɢɜɧɨɫɬɶɸ
ܺ
˅˞˘
ɬɪɚɧɡɢɫɬɨɪɚ, ɚ ɨɩɬɢɦɚɥɶɧɨɟ ɡɧɚɱɟɧɢɟ
ɨɩɬɢɦɚɥɶɧɨɫɬɢ ɭɫɢɥɢɬɟɥɹ — ɧɚɢɛɨɥɶɲɚɹ ɜɵɯɨɞɧɚɹ ɦɨɳɧɨɫɬɶ, ɤɨɷɮɮɢɰɢɟɧɬ
˅˘
˅˞˘
˅˘ଵ
=
ൗ , (2.7)
ࡵ
˅˘ଵ
˅˘
= ܴ
(2.8)
ˋ˔˕
ʠʥ
ǡ ࡵ
െɤɨɦɩɥɟɤɫɧɵɟ ɚɦɩɥɢɬɭɞɵ ɩɟɪɜɨɣ
˅˞˘
< 0. Ɇɧɢɦɚɹ ɱɚɫɬɶ
˅˞˘
ȁ
ȁ
ܴ
ɡɚɜɢɫɢɬ ɨɬ ɤɪɢɬɟɪɢɹ
˅˞˘
38
˅˞˘
=
2. ɍɫɢɥɢɬɟɥɢ ɦɨɳɧɨɫɬɢ
ɭɫɢɥɟɧɢɹ, ɄɉȾ, ɦɢɧɢɦɚɥɶɧɵɣ ɤɨɷɮɮɢɰɢɟɧɬ ɲɭɦɚ ɢ ɞɪ. Ɉɩɬɢɦɚɥɶɧɵɣ ɪɟɠɢɦ
ɪɚɛɨɬɵ ɬɪɚɧɡɢɫɬɨɪɚ ɨɛɟɫɩɟɱɢɜɚɟɬɫɹ, ɟɫɥɢ ɬɪɚɧɡɢɫɬɨɪ ɧɚɝɪɭɠɟɧ ɧɚ
ɤɨɦɩɥɟɤɫɧɨɟ ɫɨɩɪɨɬɢɜɥɟɧɢɟ
= |ܴ
ܼ
ˑ˒˕
˅˞˘
| — j ܺ
˅˞˘
ȼɵɯɨɞɧɚɹ ɫɨɝɥɚɫɭɸɳɚɹ ɰɟɩɶ ɩɪɟɨɛɪɚɡɭɟɬ ɫɨɩɪɨɬɢɜɥɟɧɢɟ ɧɚɝɪɭɡɤɢ
ɭɫɢɥɢɬɟɥɹ ܴ
ɜ ɤɨɦɩɥɟɤɫɧɨɟ ɫɨɩɪɨɬɢɜɥɟɧɢɟܼ
ː
. ɉɪɢ ɷɬɨɦ, ɤ ɫɬɨɤɭ
ˑ˒˕
ɬɪɚɧɡɢɫɬɨɪɚ ɨɤɚɡɵɜɚɟɬɫɹ ɩɨɞɤɥɸɱɟɧɧɵɦ ɜɯɨɞɧɨɟ ɫɨɩɪɨɬɢɜɥɟɧɢɟ ɜɵɯɨɞɧɨɣ
ɫɨɝɥɚɫɭɸɳɟɣ ɰɟɩɢ
˅˞˘
= ܼ
ܼ
ʠʥ
ˑ˒˕
ɋ ɰɟɥɶɸ ɦɢɧɢɦɢɡɚɰɢɢ ɩɨɬɟɪɶ ɦɨɳɧɨɫɬɢ ɫɨɝɥɚɫɭɸɳɢɟ ɰɟɩɢ ɜɵɩɨɥɧɹɸɬ ɛɟɡ
ɢɫɩɨɥɶɡɨɜɚɧɢɹ ɨɦɢɱɟɫɤɢɯ ɫɨɩɪɨɬɢɜɥɟɧɢɣ. ɉɪɟɨɛɪɚɡɨɜɚɧɢɹ ܼ
ɞɨɥɠɧɵ ɨɫɭɳɟɫɬɜɥɹɬɶɫɹ ɜɨ ɜɫɟɦ ɱɚɫɬɨɬɧɨɦ ɞɢɚɩɚɡɨɧɟ ɪɚɛɨɬɵ ɭɫɢɥɢɬɟɥɹ.
ܼ
ˑ˒˕
˅˘
ɜ ܴ
˅˘
ʠʥ
ɢ ܴ
ɜ
ː
ȼ ɩɪɨɫɬɟɣɲɟɦ ɫɥɭɱɚɟ ɪɚɛɨɬɵ ɭɫɢɥɢɬɟɥɹ ɧɚ ɨɞɧɨɣ ɱɚɫɬɨɬɟ ɫɨɝɥɚɫɭɸɳɢɟ ɰɟɩɢ
ɦɨɝɭɬ ɛɵɬɶ ɜɵɩɨɥɧɟɧɵ ɜ ɜɢɞɟ Ƚ-, Ɍ- ɢɥɢ ɉ- ɨɛɪɚɡɧɵɯ LC — ɰɟɩɨɱɟɤ. ȼ
ɲɢɪɨɤɨɩɨɥɨɫɧɵɯ ɭɫɢɥɢɬɟɥɹɯ ɫɨɝɥɚɫɭɸɳɢɟ ɰɟɩɢ ɢɦɟɸɬ ɜɢɞ ɩɨɥɨɫɧɨɩɪɨɩɭɫɤɚɸɳɢɯ ɮɢɥɶɬɪɨɜ.
Ɉɰɟɧɤɚ ɤɚɱɟɫɬɜɚ ɫɨɝɥɚɫɨɜɚɧɢɹ ɫɨɩɪɨɬɢɜɥɟɧɢɣ.
Ʉɚɱɟɫɬɜɨ ɫɨɝɥɚɫɨɜɚɧɢɹ ɜɯɨɞɧɨɣ ɋɐ ɨɩɪɟɞɟɥɹɟɬɫɹ ɞɨɩɭɫɬɢɦɵɦ ɦɨɞɭɥɟɦ
ɤɨɷɮɮɢɰɢɟɧɬɚ ɨɬɪɚɠɟɧɢɹ ɧɚɩɪɹɠɟɧɢɹ ɨɬ ɬɪɚɧɡɢɫɬɨɪɚ
ࢁ
ˑ˕˓
߁ =ȁ
൘
|,
ࢁ
˒˃ˇ
ɝɞɟ ࢁ
ɬɪɚɧɡɢɫɬɨɪɚ ɢɡ ɢɫɬɨɱɧɢɤɚ ɤɨɥɟɛɚɧɢɣ, ࢁ
— ɤɨɦɩɥɟɤɫɧɚɹ ɚɦɩɥɢɬɭɞɚ ɧɚɩɪɹɠɟɧɢɹ, ɩɚɞɚɸɳɚɹ ɧɚ ɜɯɨɞ
˒˃ˇ
— ɤɨɦɩɥɟɤɫɧɚɹ ɚɦɩɥɢɬɭɞɚ
ˑ˕˓
ɧɚɩɪɹɠɟɧɢɹ, ɨɬɪɚɠɟɧɧɚɹ ɨɬ ɬɪɚɧɡɢɫɬɨɪɚ. ɉɪɟɞɟɥɵ ɢɡɦɟɧɟɧɢɹ Ƚ: 0 < Ƚ < 1.
Ⱦɪɭɝɢɦ ɩɨɤɚɡɚɬɟɥɟɦ ɤɚɱɟɫɬɜɚ ɫɨɝɥɚɫɨɜɚɧɢɹ ɹɜɥɹɟɬɫɹ ɤɨɷɮɮɢɰɢɟɧɬ ɫɬɨɹɱɟɣ
ɜɨɥɧɵ ɧɚɩɪɹɠɟɧɢɹ ɜ ɥɢɧɢɢ, ɩɨɞɜɨɞɹɳɟɣ ɷɥɟɤɬɪɨɦɚɝɧɢɬɧɵɟ ɤɨɥɟɛɚɧɢɣ ɤ
ɬɪɚɧɡɢɫɬɨɪɭ:
ଵାʒ
݇
=
ଵିʒ
ǡ
ɩɪɢ ɷɬɨɦ, 1< ݇
< λ.
˔˅
˔˅
Ɍɪɟɬɢɣ ɩɨɤɚɡɚɬɟɥɶ ɤɚɱɟɫɬɜɚ ɫɨɝɥɚɫɨɜɚɧɢɹ — ɜɨɡɜɪɚɬɧɵɟ ɩɨɬɟɪɢ RL
(Return Loss):
ܲ
RL =10
˒˃ˇ
൘
,
ܲ
ˑ˕˓
ɢɥɢ
39
Ɋɨɦɚɧɸɤ ȼ.Ⱥ. Ⱥɧɚɥɨɝɨɜɵɟ ɭɫɬɪɨɣɫɬɜɚ ɩɪɢɟɦɨɩɟɪɟɞɚɬɱɢɤɨɜ
RL, ɞȻ = ܲ
˒˃ˇǡˇʐ
Ȅܲ
ˑ˕˓ǡˇʐ
— ɷɬɨ ɪɚɡɧɢɰɚ ɜ ɞȻ ɦɟɠɞɭ ɦɨɳɧɨɫɬɶɸ ɤɨɥɟɛɚɧɢɣ, ɩɨɞɜɨɞɢɦɵɯ ɤ ɬɪɚɧɡɢɫɬɨɪɭ,
ɢ ɨɬɪɚɠɟɧɧɵɯ ɨɬ ɬɪɚɧɡɢɫɬɨɪɚ. ɉɨɫɤɨɥɶɤɭ
ܲ
ˑ˕˓
Ƚ =
൘
,
ܲ
ඨ
˒˃ˇ
ɬɨ
RL = — 20 ʒ, ɞȻ.
ɋɨɝɥɚɫɨɜɚɧɢɟ ɬɟɦ ɥɭɱɲɟ, ɱɟɦ ɦɟɧɶɲɟ ɤɨɷɮɮɢɰɢɟɧɬ ɨɬɪɚɠɟɧɢɹ Ƚ, ɦɟɧɶɲɟ
݇
ɢ ɛɨɥɶɲɟ ɜɟɥɢɱɢɧɚ RL. (ɇɚɩɪɢɦɟɪ, ɜɨɡɦɨɠɧɵɟ ɡɧɚɱɟɧɢɹ ɩɨɤɚɡɚɬɟɥɟɣ
˔˅
ɤɚɱɟɫɬɜɚ ɫɨɝɥɚɫɨɜɚɧɢɹ: Ƚ= 0,2, ݇
=1,5, RL = 20,8 ɞȻ).
˔˅
Ⱥɧɚɥɨɝɢɱɧɨ ɨɰɟɧɢɜɚɟɬɫɹ ɫɨɝɥɚɫɨɜɚɧɢɟ ɜɵɯɨɞɧɨɣ ɋɐ. ɉɨɤɚɡɚɬɟɥɹɦɢ
ɫɨɝɥɚɫɨɜɚɧɢɹ ɫɥɭɠɚɬ: ɦɨɞɭɥɶ ɤɨɷɮɮɢɰɢɟɧɬɚ ɨɬɪɚɠɟɧɢɹ ɨɬ ɜɵɯɨɞɚ ɬɪɚɧɡɢɫɬɨɪɚ
ɢ ɜɵɯɨɞɧɵɟ ɜɨɡɜɪɚɬɧɵɟ ɩɨɬɟɪɢ, ɤɨɷɮɮɢɰɢɟɧɬ ɫɬɨɹɱɟɣ ɜɨɥɧɵ ɧɚɩɪɹɠɟɧɢɹ ɜ
ɥɢɧɢɢ, ɜɟɞɭɳɟɣ ɤ ɧɚɝɪɭɡɤɟ.
ȼɨɡɦɨɠɧɨɫɬɢ ɲɢɪɨɤɨɩɨɥɨɫɧɨɝɨ ɫɨɝɥɚɫɨɜɚɧɢɹ.
ɉɪɢ ɩɨɫɬɪɨɟɧɢɢ ɜɯɨɞɧɨɣ ɲɢɪɨɤɨɩɨɥɨɫɧɨɣ ɫɨɝɥɚɫɭɸɳɟɣ ɰɟɩɢ ɠɟɥɚɬɟɥɶɧɨ
ɨɬɜɟɬɢɬɶ ɧɚ ɜɨɩɪɨɫ: ɜ ɤɚɤɨɣ ɩɨɥɨɫɟ ɱɚɫɬɨɬ ɦɨɠɧɨ ɨɫɭɳɟɫɬɜɢɬɶ ɫɨɝɥɚɫɨɜɚɧɢɟ ɫ
ɠɟɥɚɟɦɨɣ ɜɟɥɢɱɢɧɨɣ ɤɨɷɮɮɢɰɢɟɧɬɚ ɨɬɪɚɠɟɧɢɹ, ɟɫɥɢ ɢɡɜɟɫɬɟɧ ɢɦɩɟɞɚɧɫ
ɬɪɚɧɡɢɫɬɨɪɚ ܼ
. Ʉɨɷɮɮɢɰɢɟɧɬ ɨɬɪɚɠɟɧɢɹ ɨɩɪɟɞɟɥɹɟɬɫɹ ɫɥɟɞɭɸɳɟɣ ɮɨɪɦɭɥɨɣ
˅˘
˅˘ିோ
ˋ˔˕
Ƚ =
˅˘ାோ
ˋ˔˕
ȿɫɥɢ ɬɪɟɛɭɟɬɫɹ ɫɨɝɥɚɫɨɜɚɬɶ ɬɪɚɧɡɢɫɬɨɪɚ ɧɚ ɨɞɧɨɣ ɱɚɫɬɨɬɟ, ɬɨ ɦɧɢɦɚɹ ɱɚɫɬɶ
ɜɯɨɞɧɨɝɨ ɢɦɩɟɞɚɧɫɚ ɬɪɚɧɡɢɫɬɨɪɚ ɦɨɠɟɬ ɛɵɬɶ ɫɤɨɦɩɟɧɫɢɪɨɜɚɧɚ,
ɞɟɣɫɬɜɢɬɟɥɶɧɚɹ ɱɚɫɬɶ ܴ
ɩɪɟɨɛɪɚɡɨɜɚɧɚ ɜ ܴ
˅˘
ɢ, ɬɚɤɢɦ ɨɛɪɚɡɨɦ, Ƚ=0, ɬɨ ɟɫɬɶ,
ˋ˔˕
ɜɨɡɦɨɠɧɨ ɩɨɥɧɨɟ ɫɨɝɥɚɫɨɜɚɧɢɟ. ɇɚɥɢɱɢɟ ɦɧɢɦɨɣ ɱɚɫɬɢ ɫɨɝɥɚɫɭɟɦɨɝɨ
ɢɦɩɟɞɚɧɫɚ ܼ
ɩɪɢɜɨɞɢɬ ɤ ɬɨɦɭ, ɱɬɨ ɜ ɩɨɥɨɫɟ ɱɚɫɬɨɬ ο݂ = ݂
˅˘
௫
Ȅ݂
ɩɨɥɧɨɝɨ
ɫɨɝɥɚɫɨɜɚɧɢɹ ɛɵɬɶ ɧɟ ɦɨɠɟɬ ɢ ɩɪɢɯɨɞɢɬɫɹ ɦɢɪɢɬɶɫɹ ɫ ɬɟɦ, ɱɬɨ Ƚ > 0.
ɋɜɹɡɶ ɩɨɥɭɱɚɟɦɨɝɨ ɦɨɞɭɥɹ ɤɨɷɮɮɢɰɢɟɧɬɚ ɨɬɪɚɠɟɧɢɹ Ƚ ɫ ɦɚɤɫɢɦɚɥɶɧɨɣ
ɩɨɥɨɫɨɣ ɭɫɢɥɢɜɚɟɦɵɯ ɱɚɫɬɨɬ ο݂ ɨɩɪɟɞɟɥɹɟɬɫɹ ɜɵɜɨɞɨɦ ɢɡ ɬɟɨɪɢɣ Ȼɨɞɟ ɢ
Ɏɚɧɨ, ɫɨɝɥɚɫɧɨ ɤɨɬɨɪɨɦɭ ɩɨɥɨɫɚ ɱɚɫɬɨɬ ɨɝɪɚɧɢɱɢɜɚɟɬɫɹ ɫɥɟɞɭɸɳɢɦ ɭɫɥɨɜɢɟɦ
ିଵ
ο݂ሺʹ߬
ͳ
ൗሻ
,
ʒ
ɝɞɟ ߬ — ɩɨɫɬɨɹɧɧɚɹ ɜɪɟɦɟɧɢ ɫɨɝɥɚɫɭɟɦɨɝɨ ɢɦɩɟɞɚɧɫɚ, ɤɨɬɨɪɵɣ ɩɪɟɞɫɬɚɜɥɟɧ
ɥɢɛɨ ɩɨɫɥɟɞɨɜɚɬɟɥɶɧɵɦ ɫɨɟɞɢɧɟɧɢɟɦ R ɢ L, ɥɢɛɨ ɩɚɪɚɥɥɟɥɶɧɵɦ ɫɨɟɞɢɧɟɧɢɟɦ
R ɢ ɋ, ɬɨ ɟɫɬɶ ߬= RC ɢɥɢ ߬ =
ܮ
ൗ .
ܴ
40
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