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樓主 |
發表於 2009-11-27 00:03:48
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只看該作者
有的,只是要看產品規格屬性有無定義, z9 \, e' h% M0 B2 X9 P
其中,最主要的乃是eye diagram的定義) O+ X- f. z. a3 [$ L' _
像SATA, or USB就有明確定義TX的 ...
" @7 D; {$ A9 q& `finster 發表於 2009-11-26 09:26 PM
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聽版主你這麼說,我是可以藉由欲接受我方TX的RX端之規格,去推算TX端的合理範圍囉?
' V' m( y5 m/ B: F: l8 F4 O因為規格上沒有定義關於jitter方面的限制。0 r( `7 A" C1 H' U
以下是對方rx的定義, d- N1 ]3 m* T4 j* R# z4 ?5 F
總頻寬3MHz,子頻寬300kHz* c6 H0 X8 `& x
Programmer / Controller Unit 3 Y- f( |; H; ^+ @1 z1 w- ^
Receiver noise bandwidth 200 kHz ) H7 Z, i a1 w1 [2 n
Antenna Gain Tx/Rx 2 dBi
7 H2 Y* U, o7 D3 pPower Into Antenna -22 dBm
( a+ j, z, k& M0 N: e1 s/ qTx Power -20 dBm EIRP ( [$ U# N3 N0 ~$ l( c" X
Required SNR 14 dB
9 I9 b) k' }( ?; T% fNoise Floor -101 dBm
$ H# l6 I* i0 m, ^. q" N6 l* {Ambient noise at receiver input 20 dB above kTB , F) e6 v, f. c6 {# F7 ]+ S8 o. B
Receiver noise figure 4 dB 6 Y( L* @* K% T# G
跟傳輸上的耗損
: I; ^* y# r# u* \* eTransmission Losses
7 M% d: j6 V D/ M% M% ^" l7 E. CFree space loss at 2 meters 30.5 dB ) p: F% e- G- _7 i9 w) a: ^7 l
Fade margin (with diversity) 10 dB ) B, V7 r9 E( I9 W2 Y( o! \$ i7 x
Excess loss (polarisation, etc.) 15 dB
# Z) [4 `$ V( F* R# f' eBuilding penetration loss 20 dB |
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