Rambler's Top100Astronet    
  po tekstam   po klyuchevym slovam   v glossarii   po saitam   perevod   po katalogu
 
Na saite
Astrometriya
Astronomicheskie instrumenty
Astronomicheskoe obrazovanie
Astrofizika
Istoriya astronomii
Kosmonavtika, issledovanie kosmosa
Lyubitel'skaya astronomiya
Planety i Solnechnaya sistema
Solnce

Belyi shum
6.08.2001 0:00 |

Belyi shum - shum, vremya korrelyacii kotorogo mnogo men'she vseh harakternyh vremen fizicheskoi sistemy. Matematicheskoi model'yu belogo shuma sluzhit sluchainyi process $\xi(t)$ $(\lt\xi(t)\gt=0)$ s korrelyacionnoi funkciei
$\Gamma(t,\tau)=\lt\xi(t+\tau)\xi(t)\gt=\sigma^2(t)\delta(\tau)$, (1)

gde $\delta(\tau)$ - del'ta-funkciya, $\le...\gt)$ - statisticheskoe usrednenie. $\sigma^2(t)$ - intensivnost' belogo shuma. V sluchae stacionarnogo processa $\sigma^2(t)=const$, prichem korrelyacionnoi funkcii (1) otvechayut ravnomernyi spektr
$\tilde{\Gamma}(\omega)=(2\pi)^{-1}\int_{-\infty}^{\infty}\Gamma(\tau) exp(-i\omega\tau)d\tau=\sigma^2/2\pi$, (2)

ravnoe nulyu vremya korrelyacii $\tau_k$ i v sootvetstvii s sootnosheniem neopredelennosti $\tau_k\Delta\omega\gt1$ beskonechnaya shirina spektra $\Delta\omega$.
Model' belogo shuma ispol'zuyut dlya opisaniya vozdeistviya shumov s malym vremenem korrelyacii na fizicheskie sistemy (signaly), obladayushie konechnoi shirinoi polosy propuskaniya (spektra), v predelah kotoroi spektr real'nogo shuma mozhno schitat' priblizhenno ravnomernym. Primerom belogo shuma yavlyaetsya drobovoi shum, vremya korrelyacii kotorogo opredelyaetsya vremenem proleta elektrona ot katoda k anodu. Spektr drobovogo shuma ravnomeren do chastoty $\sim 10^8$ Gc. Drugoi primer - teplovoi shum, spektr kotorogo ravnomeren v tom intervale chastot, gde postoyanno soprotivlenie istochnika shuma. V oblasti slyshimyh chastot primerom belogo shuma yavlyaetsya shum vodopada.

Glossarii Astronet.ru


Publikacii s klyuchevymi slovami: fur'e spektr - belyi shum - shum
Publikacii so slovami: fur'e spektr - belyi shum - shum
Karta smyslovyh svyazei dlya termina BELY' ShUM
Sm. takzhe:

Ocenka: 2.8 [golosov: 67]
 
O reitinge
Versiya dlya pechati Raspechatat'

Astronet | Nauchnaya set' | GAISh MGU | Poisk po MGU | O proekte | Avtoram

Kommentarii, voprosy? Pishite: info@astronet.ru ili syuda

Rambler's Top100 Yandeks citirovaniya