I te wa e tukuna ana te tohu auau reo irirangi teitei/ngaruiti ki roto i te PCB ara iahiko, ko te mate i puta mai i te ara iahiko tonu me nga rawa ara iahiko ka kore e kore ka puta he wera. Ko te nui o te mate, ko te teitei o te mana e haere ana i roto i te papanga PCB, me te nui ake o te wera i hangaia. Ka nui ake te pāmahana whakahaere o te ara iahiko i te uara whakatau, ka raru pea te ara iahiko. Hei tauira, ko te tawhā whakahaere angamaheni MOT, e tino mohiotia ana i roto i nga PCB, ko te pāmahana whakahaere teitei. Ka nui ake te pāmahana whakahaere i te MOT, ka raru te mahi me te pono o te ara iahiko PCB. Ma te whakakotahitanga o te whakatauira hiko me nga inenga whakamatautau, ma te mohio ki nga ahuatanga waiariki o nga PCB ngaruiti RF ka taea te karo i te paheketanga o te mahi ara iahiko me te paheketanga pono na te nui o te wera.

Ma te mohio me pehea te ngaronga o te whakauru ki roto i nga rauemi ara iahiko ka pai ake te whakamaarama i nga mea nui e pa ana ki te mahi waiariki o nga iahiko PCB auau teitei. Ka tangohia e tenei tuhinga te ara iahiko raina whakawhiti microstrip hei tauira ki te matapaki i nga tauhokohoko e pa ana ki te mahi wera o te ara iahiko. I roto i te ara iahiko microstrip me te hanganga PCB-taha-rua, ko nga mate ko te mate dielectric, te ngaro o te kaiarahi, te mate iraruke, me te ngaronga rerenga. He nui te rereketanga i waenga i nga waahanga mate rereke. He iti noa nga tuunga, he iti rawa te ngaronga o nga iahiko PCB auau teitei. I roto i tenei tuhinga, i te mea he iti rawa te uara o te mate rerenga, ka warewarehia mo tenei wa.

Te mate iraruke

Radiation loss depends on many circuit parameters such as operating frequency, circuit substrate thickness, PCB dielectric constant (relative dielectric constant or εr) and design plan. As far as design schemes are concerned, radiation loss often stems from poor impedance transformation in the circuit or electromagnetic waves in the circuit. The difference in transmission. Circuit impedance transformation area usually includes signal feed-in area, step impedance point, stub and matching network. Reasonable circuit design can realize smooth impedance transformation, thereby reducing the radiation loss of the circuit. Of course, it should be realized that there is the possibility of impedance mismatch leading to radiation loss at any interface of the circuit. From the point of view of operating frequency, usually the higher the frequency, the greater the radiation loss of the circuit.

Ko nga tawhā o nga rauemi ara iahiko e pa ana ki te ngaronga iraruke ko te te nuinga o te dielectric me te matotoru o te papanga PCB. Ko te matotoru o te tïpako iahiko, ka nui ake pea te mate iraruke; ka iti ake te εr o te papanga PCB, ka nui ake te mate iraruraru o te ara iahiko. Ko te taumahatanga o nga ahuatanga o nga rawa, ka taea te whakamahi i nga taputapu ara iahiko angiangi hei arai i te mate iraruke na te iti o nga rauemi ara iahiko εr. Ko te awe o te matotoru o te tïpako ara iahiko me te εr ki te ngaronga iraruke ara iahiko na te mea he mahi e whakawhirinaki ana ki te auau. Ki te kore e neke ake te matotoru o te taputapu ara iahiko i te 20mil me te iti ake o te auau whakahaere i te 20GHz, he iti rawa te mate iraruraru o te ara iahiko. I te mea he iti ake te nuinga o nga tauira ara iahiko me nga ine ine i roto i tenei tuhinga i te 20GHz, ka kore e arohia e te matapaki i tenei tuhinga te awe o te mate iraruke i runga i te whakamahana ara iahiko.

Whai muri i te kore e aro ki te ngaronga iraruke i raro iho i te 20GHz, ko te ngaronga whakaurunga o te iahiko raina whakawhiti microstrip e rua nga waahanga: te mate dielectric me te ngaronga kawe. Ko te wahanga o nga mea e rua e whakawhirinaki ana ki te matotoru o te taputapu ara iahiko. Mo nga taputapu angiangi, ko te ngaro o te kaiarahi te waahanga matua. He maha nga take, he uaua ki te matapae tika i te ngaronga o te kaiarahi. Hei tauira, ko te taratara o te mata o te kaikawe he nui te awe ki nga ahuatanga tuku o nga ngaru hiko. Ko te taratara o te mata o te pepa parahi e kore e huri noa i te ngaru hiko hiko o te ara iahiko microstrip, engari ka nui ake te ngaro o te kaikawe o te ara iahiko. Na te paanga o te kiri, ko te awe o te taratara o te pepa parahi i runga i te ngaronga o te kaikawe ka whakawhirinaki ki te auau. Ko te ahua 1 e whakataurite ana i te ngaronga whakaurunga o te 50 ohm microstrip raina whakawhiti iahiko i runga i nga momo matotoru PCB, he 6.6 mils me te 10 mils, ia.

The simulation results are obtained using Rogers Corporation’s MWI-2010 microwave impedance calculation software. The MWI-2010 software quotes the analytical equations in the classic papers in the field of microstrip line modeling. The test data in Figure 1 is obtained by the differential length measurement method of a vector network analyzer. It can be seen from Fig. 1 that the simulation results of the total loss curve are basically consistent with the measured results. It can be seen from the figure that the conductor loss of the thinner circuit (the curve on the left corresponds to a thickness of 6.6 mil) is the main component of the total insertion loss. As the circuit thickness increases (the thickness corresponding to the curve on the right is 10mil), the dielectric loss and the conductor loss tend to approach, and the two together constitute the total insertion loss.

The circuit material parameters used in the simulation model and the actual circuit are: dielectric constant 3.66, loss factor 0.0037, and copper conductor surface roughness 2.8 um RMS. When the surface roughness of the copper foil under the same circuit material is reduced, the conductor loss of the 6.6 mil and 10 mil circuits in Figure 1 will be significantly reduced; however, the effect is not obvious for the 20 mil circuit. Figure 2 shows the test results of two circuit materials with different roughness, namely Rogers RO4350B™ standard circuit material with high roughness and Rogers RO4350B LoPro™ circuit material with low roughness.

For thinner substrates, the use of smooth copper foil can significantly reduce the insertion loss. For the 6.6mil substrate, the insertion loss is reduced by 0.3 dB due to the use of smooth copper foil at 20GHz; the 10mil substrate is reduced by 0.22 dB at 20GHz; and the 20mil substrate, the insertion loss is only reduced by 0.11 dB.

This means that when the circuit is fed with a certain amount of RF microwave power, the thinner the circuit will generate more heat. When comprehensively weighing the issue of circuit heating, on the one hand, a thinner circuit generates more heat than a thick circuit at high power levels, but on the other hand, a thinner circuit can obtain more effective heat flow through the heat sink. Keep the temperature relatively low.

Hei whakaoti i te raruraru whakawera o te ara iahiko, me whai i te ara iahiko angiangi pai nga ahuatanga e whai ake nei: te iti o te ngaronga o te rauemi ara iahiko, te mata angiangi parahi maeneene, te iti o te εr me te kawe werawera teitei. Ka whakatauritea ki nga rauemi ara iahiko o te εr teitei, ko te whanui o te kaitarai o te impedance kotahi i whiwhi i raro i te ahua o te εr iti ka nui ake, he pai ki te whakaiti i te ngaro o te kaikawe o te ara iahiko. Mai i te tirohanga o te tohanga wera iahiko, ahakoa ko te nuinga o nga taputapu ara iahiko PCB teitei he tino ngoikore te kawe i te waiariki e pa ana ki nga kaikawe, ko te kawe wera o nga rauemi ara iahiko he tohu tino nui.

He maha nga korero mo te kawe wera o nga taputapu ara iahiko kua whakamaramatia i roto i nga tuhinga o mua, a ka whakahuahia e tenei tuhinga etahi hua me nga korero mai i nga tuhinga o mua. Hei tauira, ko te wharite e whai ake nei me te Whakaahua 3 he awhina ki te mohio ki nga ahuatanga e pa ana ki te mahi waiariki o nga rauemi ara iahiko PCB. I roto i te whārite, ko te k te kawe i te waiariki (W/m/K), ko A te rohe, ko te TH te pāmahana o te puna wera, ko te TC te pāmahana o te puna makariri, ko L te tawhiti i waenga i te puna wera me te puna makariri.