Aane. Nanso, na antenna nhyehyɛe ahorow a edi kan no de nneɛma a ɛma aduan a ɛyɛ tratraa a ɛnyɛ nhama a ɛyɛ coaxial di dwuma.
Ɛsɛ sɛ wɔte RF coaxial nhama ase wɔ afã abien.
RF: RF kyerɛ electromagnetic frequency a ɛtumi hyerɛn kɔ ahunmu, ɛfiri 300kHz kɔsi 300GHz.
RF yɛ radio frequency current, asɛmfua tiawa a ɛkyerɛ electromagnetic asorɔkye a ɛsesa frequency a ɛkorɔn-.
Alternating current a ɛsakra nnu mpɛn 1000 wɔ sekan biara mu no, wɔfrɛ no low-frequency current, na nea ɛsakra bɛboro mpɛn 10000 wɔ sekan biara mu no, wɔfrɛ no high-frequency current. RF yɛ saa a ɛkorɔn-frequency current.
RF (300K-300G) yɛ frequency band a ɛkorɔn wɔ frequency a ɛkorɔn (ɛboro 10K) kwan no mu.
Wɔ ɛlɛtrɔnik nkyerɛkyerɛ mu no, sɛ anyinam ahoɔden fa conductor bi mu a, magnetic field bi twa conductor no ho hyia; sɛ anyinam ahoɔden a ɛsesa fa conductor bi mu a, anyinam ahoɔden a ɛsesa twa conductor no ho hyia. Wɔfrɛ eyi sɛ anyinam ahoɔden asorɔkye.
Electromagnetic asorɔkye a ne frequency nnu 100kHz no twetwe Asase ani na entumi mfa nkɔ yiye. Nanso, anyinam ahoɔden asorɔkye a ne frequency boro 100kHz tumi trɛw fa mframa mu na ionosphere a ɛwɔ wim akyi ano no da no adi, na ɛma wotumi de nkrasɛm kɔ akyirikyiri-.
Yɛfrɛ electromagnetic asorɔkye a ɛkorɔn-frequency a ɛwɔ akyirikyiri-akyirikyiri nkrasɛm tumi radio frequency (RF).
Wɔde RF mfiridwuma di dwuma kɛse wɔ nkitahodi a wɔmfa nhama nkɔ mu; cable television nhyehyɛe ahorow de RF nkrasɛm di dwuma.
Coaxial cable: Esiane sɛ conductor abien no (inner conductor/outer conductor) no nyɛ asymmetrical wɔ asase ho, a emu conductor biako wɔ axis a cylindrical outer conductor foforo no so nti, wɔfrɛ no "coaxial cable."
Coaxial cables su bi ne sɛ electromagnetic field no titiriw na wɔato akyi conductor no mu, na ɛma wotumi de di dwuma wɔ frequency a ɛkorɔn mu.
Hyɛ no nsow: Coaxial cable akyi conductor no yɛ conductor ne shielding layer (ɛyɛ adwuma sɛ loop na ɛma anti-interference dwumadie).
Wɔfrɛ coaxial cable a wɔde di dwuma de RF nsɛnkyerɛnne kɔ "RF coaxial cable."
Wɔde nsɛnkyerɛnne a antena no nya no nam feeder line so kɔ anim, na sɛnkyerɛnne a efi anim no nso fa feeder line no so kɔ mfiri ahorow a wogye no so.
Mprempren, yɛtaa hu nkitahodi ne nkrasɛm feeders a wɔde di dwuma wɔ signal amplification nhyehyɛe te sɛ first-line wireless signal towers (China Mobile, China Unicom, China Telecom, ne nea ɛkeka ho), tunnels, ne basements.