Fizikisi Yekutanga Yekutaurirana Kwenhare
Kutaurirana nefoni inzira yekutumira ruzivo kubva kune imwe nzvimbo kuenda kune imwe uchishandisa nzira chaiyo, ingave yakabatana newaya kana isina waya. Seri kwetekinoroji yatinoshandisa zuva nezuva - nharembozha, Wi-Fi, redhiyo, terevhizheni, uye kunyange masateliti - ndiyo nheyo huru dzemuviri. Kunzwisisa fizikisi huru yekutaurirana kunoreva kunzwisisa kuti masaini anogadzirwa sei, anotakurwa nemafungu emagetsi, anotungamirirwa nenzira yekutumira, uye obva agamuchirwazve muruzivo runonzwisisika.
1. Zviratidzo neRuzivo: Kubva paMashoko kuenda kumaSaivi
Mukutaurirana nefoni, ruzivo rwuri mukati memeseji (izwi, mashoko, mifananidzo, vhidhiyo), nepo chiratidzo chiri chimiro chemuviri chinotakura ruzivo irworwo. Chiratidzo chinogona kuva voltage yemagetsi mutambo, shanduko musimba rechiedza mufiber ye optical, kana electromagnetic wave mumhepo.
Mufizikisi, zviratidzo zvinowanzotsanangurwa semabasa enguva, semuenzaniso \(x(t)). Zviratidzo zveanalog audio zvine waveform inoenderera mberi, nepo zviratidzo zvedhijitari zvine mazinga akasiyana (semuenzaniso, 0 na1). Kushandurwa kubva paanalog kuenda kudhijitari kunoitwa kuburikidza nesampling uye quantization, izvo zvine chekuita nepfungwa yezviratidzo uye miganhu yemuviri yezvigadzirwa zvemagetsi.
2. Mafungu eElectromagnetic seVatakuri
Chinonyanya kukosha pakukurukurirana kwemazuva ano mafungu emagetsi. Zvinoenderana nedzidziso yaMaxwell, simba remagetsi rinoshanduka rinogadzira simba remagineti uye zvinopesana, zvichigadzira mafungu anogona kupararira kunyangwe ari muvacuum. Kumhanya kwemafungu emagetsi ari muvacuum ndekwekuti:
\[
c \inenge 3 \kawa 10^8 \ \text{m/s}
\]
Hukama huripo pakati pehuwandu (\(f\)), urefu hwenguva (\(\lambda\)), uye kumhanya kwekupararira (\(v\)) ndehwekuti:
\[
v = f\lambda
\]
Mumhepo, kumhanya kwekupararira kuri pedyo ne \(c\), nepo muzvinhu zvakaita se coaxial cable kana optical fiber, kumhanya kwacho kwakaderera nekuda kwesimba rezvinhu (permittivity uye permeability).
3. Kugoverwa kweFrequency Spectrum neBhendi
Mafungu emagetsi anofukidza huwandu hwakakura hwemasaisai eredhiyo: kubva kumasaisai eredhiyo ane masaisai mashoma kusvika kumasaisai egamma ane masaisai akawanda. Kutaurirana nefoni kunowanzo shandisa redhiyo, microwave, uye zvikamu zveinfrared zvemasaisai eredhiyo.
Mafambiro anoita zvinhu zvakawanda: kupinda kwezvipingamupinyi, nzvimbo, saizi yeantenna, uye kugona kwechiteshi. Mafambiro akaderera (semuenzaniso, AM radio) anogona kusvika kure nekuda kwe diffraction uye ionospheric reflection, nepo mafrequency akakwira (semuenzaniso, 5G mmWave) anogona kutakura data rakawanda asi anogona kuvharirwa uye ane nzvimbo pfupi.
Nekuti spectrum yacho yakaganhurirwa uye inogona kukanganiswa, nyika imwe neimwe inotonga kugoverwa kwebhendi kuitira kuti masevhisi akasiyana asapindirane.
4. Kuchinja-chinja: Kuisa Ruzivo Pamusoro Pemafungu
Zviratidzo zveruzivo hazviwanzo tumirwa "zvisina kugadzirwa" pasina kugadziriswa. Kazhinji, ruzivo runoiswa pamusoro pechiratidzo chekutakura kuburikidza nemaitiro ekuchinja. Panyama, kuchinja zvinoreva kushandura maparamita ewaya yekutakura:
1. Kuchinja kweAmplitude (AM): amplitude yemutakuri inochinjwa mushure mechiratidzo cheruzivo.
2. Kuchinja Mafambiro (FM): mafambiro emutakuri anochinja zvichienderana neruzivo.
3. Kuchinja kwechikamu (PM) / PSK (yedhijitari): chikamu chekutakura chinoshandurwa nemutengo wakati.
Kuchinja-chinja kunoita kuti kutapurirana kushande zvakanaka, kunoderedza kupindirana, uye kunobvumira vashandisi vakawanda kugovana spectrum kuburikidza nenzira dzakadai seFM multiplexing, OFDM, kana spread spectrum.
5. Simba, Kuderedza Mvura, uye Mutemo weInverse Square
Mukutumira kusina waya, simba rechiratidzo rinogamuchirwa rinoderera nedaro. Zvichitaurwa zviri nyore, kune sosi inopenya zvakaenzana, simba resimba rinotevedzera mutemo we inverse square:
\[
I \propto \frac{1}{r^2}
\]
Zvisinei, munyika chaiyo, kupararira kwesimba kunokanganiswawo nekufungisisa, kupararira, kunyudzwa, uye kuwanda kwesimba. Mumatambo, kuderedzwa kwesimba kunonzi attenuation, inowanzo ratidzwa muma decibels (dB). Fomura yakajairika ye power ratio ndeiyi:
\[
\text{dB} = 10 \log_{10}\left(\frac{P_2}{P_1}\right)
\]
Pfungwa ye dB yakakosha zvikuru nekuti inobatsira pakuverenga kuwedzera kwe amplifier, kurasikirwa kwetambo, uye margins esystem muchimiro che logarithmic sums.
6. Ruzha uye Chiyero cheSignal to Noise Ratio (SNR)
Hapana sisitimu yekutaurirana isina kukanganiswa. Ruzha runobva kwakasiyana-siyana: kufamba kwemaerekitironi anodziya (ruzha rwekupisa), kukanganiswa kwemidziyo, kukanganiswa nevamwe vashandisi, uye kunyange zviitiko zvemumhepo.
Imwe yepfungwa dzefizikisi dzakakosha pakugamuchira masaini ndiyo Signal-to-Noise Ratio (SNR), inova chiyero chesimba remasaini kune simba reruzha. SNR yakakwira zvinoreva kuti chiratidzo chiri nyore kudzoreredza, nepo SNR yakaderera inowedzera mukana wekukanganisa kwedata.
Ruzha rwekupisa runogona kuverengerwa ne equation:
\[
N = kTB
\]
ne \(k\) Boltzmann constant, \(T\) tembiricha (Kelvin), uye \(B\) frequency bandwidth. Iyi equation inoratidza kuti bandwidth yakafara, ruzha rwunounzwa rwunowedzera, saka dhizaini yesystem inogara ichisanganisira kutengeserana pakati pekugona kwedata uye kuramba ruzha.
7. Bandwidth, Kugona kweChannel, uye Shannon Limit
Bandwidth ndiyo huwandu hwemafrequencies anoshandiswa nesignal. Mu telecommunications physics, bandwidth ine chekuita zvakananga nekuti ruzivo runogona kutumirwa nekukurumidza sei. Dzidziso yeruzivo inopa muganho mukuru kuburikidza nedzidziso yaShannon:
\[
C = B \log_2(1+\text{SNR})
\]
apo \(C\) iri kugona kwechiteshi (bits/second). Iyi haisi nzira yehunyanzvi chete, asi muganho weruzivo rwepanyama: kugona kwedata kwakanyanya kugoneka kwedata rebandwidth neSNR. Matekinoroji emazuva ano akadai se4G/5G, Wi-Fi 6/7, uye kutaurirana kwesatellite zviri kugara zvichisvika pamuganho weShannon nekunyora kodhi yechiteshi kwakaoma (kugadzirisa kukanganisa) uye modulation.
8. Kutumira Midhiya: Cable, Optical Fiber, uye Free Space
a) Tambo yemhangura (peya yakakombama, coaxial)
Mutambo dzemhangura, zviratidzo zvinopararira semafungu emagetsi anotungamirwa. Kusasimba kwemagetsi, ganda rinoita mafrequency akakwira, uye capacitance zvinokonzera kuderera uye kukanganiswa. Tambo dzeCoaxial dzinoramba kukanganiswa kupfuura mawiri akakombama nekuda kwekudzivirira kwadzo.
b) Faibha yemaziso
Optical fiber inotumira ruzivo ichishandisa chiedza, kazhinji lasers. Musimboti wayo mukuru wepanyama ndeyekuratidzwa kwemukati mese nekuda kwemusiyano we refractive index pakati pepakati necladding. Optical fiber ine attenuation yakaderera uye bandwidth yakakwira kwazvo, zvichiita kuti ive musimboti weinternet yepasi rose.
c) Kuparadzira nzvimbo pasina muripo (redhiyo nema microwave)
Mukutaurirana kusina waya, mafungu anopararira mumhepo kuburikidza nezvinhu zvakaita sekuratidzira, kupararira, uye kupararira. Pama frequency akakwira, line-of-sight inova yakakosha, saka ma antenna anowanzoiswa pashongwe kana kuti ma satellite anoshandiswa.
9. Antena: Inoshandura Current kuita Mafungu
Antena mudziyo unobatanidza masaini emagetsi nemafungu emagetsi. Kana magetsi achichinjana achipfuura nepaantena, machaji anomhanya anoburitsa mafungu emagetsi.
Hunhu hwakakosha hweantenna mufizikisi yekutaurirana dzinosanganisira:
- Kuwana (kukwira kwenzira): tarisa danda munzira yakati.
- Patani yemwaranzi: kuti simba rinoburitswa sei muchadenga.
– Polarization: kurongeka kwesimba remagetsi (rakatwasuka, rakatwasuka, rakatenderera).
Kufananidza polarization yetransmitter nereceiver kwakakosha: kusawirirana kwepolarization kunogona kuderedza simba rakagamuchirwa zvakanyanya.
10. Mhedziso: Nei Fizikisi iri Pakati Pekukurukurirana Kwenhare
Kutaurirana nefoni hakusi kwekushandisa chete kana mashandisirwo, asi kushandiswa zvakananga kwemitemo yefizikisi: mafungu emagetsi, simba nesimba, kuderera kwesimba, ruzha rwekupisa, uye kunyange miganhu yesimba reruzivo. Kuvandudzwa kwetekinoroji yekutaurirana, kubva paredhiyo yeanalog kusvika kune network dze5G uye fiber optics dzinomhanya zvakanyanya, chaizvoizvo ibasa revanhu rekudzora nekugadzirisa maitiro emafungu, zvinhu, neruzivo.
Nekunzwisisa fizikisi huru yekutaurirana, tinogona kuona kuti kufona kwese kwese, vhidhiyo yega yega, uye meseji inotumirwa imhedzisiro yekurongeka kwakarurama kwezviitiko zvechisikigo - kubva pakufamba kwemaerekitironi mumasekete, kusvika kumaphoton mufibers e optical, kusvika kumafungu eredhiyo anofamba munzvimbo yakasununguka. Kunzwisisa uku hakungobatsiri chete kune vadzidzi veinjiniya nevanoita zvehunyanzvi, asiwo kunovhura ruzivo rwekuti nyika yanhasi yakabatana sei kuburikidza nemitemo mikuru yepasirese.
