求教，中兴3g上网卡掉线的问题，型号AC582

stitchwillow

配置如下：
lsusb内容：
2 [) M1 s, I, D0 @% X9 yBus001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus001 Device 002: ID 0424:9512 Standard Microsystems Corp.
Bus001 Device 003: ID 0424:ec00 Standard Microsystems Corp.
7 t5 t! x! [" N# C6 O: ?Bus001 Device 004: ID 1a40:0101 Terminus Technology Inc. 4-Port HUB
Bus001 Device 005: ID 148f:3070 Ralink Technology, Corp. RT2870/RT3070 WirelessAdapter
Bus001 Device 006: ID 04b3:3025 IBM Corp. NetVista Full Width Keyboard
Bus001 Device 009: ID 19d2:0152 ZTE WCDMA Technologies MSM

vi /etc/usb_modeswitch.conf
将里面内容改为：
+ {/ b7 U( V5 k- n9 WDisableSwitching=0
DefaultVendor= 0x19d2
DefaultProduct= 0x0026
' P, O3 d8 U8 W: _5 X( ]; WTargetVendor= 0x19d2
9 V1 k, f& D% S/ f& [+ F/ i; lTargetProduct= 0x0152
MessageContent="5553424312345678240000008000061b000000020000000000000000000000"
) Q) t/ n% s/ y$ W0 a& K: XCheckSuccess=5
HuaweiMode=0

运行usb_modeswitch -W -c /etc/usb_modeswitch.conf
+ X3 b' j2 J$ ]8 q' s* n
vi /etc/wvdial.conf
内容为：
$ l6 x# d0 i% [[Dialer 3g]
Init1 = ATZ
Init2 = ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0
Stupid Mode = 1
! p. I/ v. a/ m& D4 |- f; zModem Type = Analog Modem
ISDN = 0
# k" P6 j9 z6 Y4 o, q# dNew PPPD = yesPhone = #777
; Y) }- O) C3 D) T: NModem = /dev/ttyUSB0
Username = ctnet@mycdma.cn
$ Q4 W  H1 a" SPassword= vnet.mobi
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6 P6 q3 a# `8 L/ Mwvdial 3g拨号正常上网。
2 H+ a& S" H  a, A时间久了不定时掉线
掉线提示：A modem hung up the phone (exit code 16)
6 }3 u& P* O3 g' g& u
( o6 S2 [1 G4 U9 w# ydmesg 显示多出如下信息：
) Z  {9 ?' S; I3 E2 ^, c. i[28924.835673] option1 ttyUSB0: option_instat_callback: error -108
[28924.847101] option1 ttyUSB0: GSM modem (1-port) converter now disconnected from ttyUSB0
[28924.847266] option 1-1.3.2:1.0: device disconnected
[28924.851020] option1 ttyUSB1: GSM modem (1-port) converter now disconnected from ttyUSB1
[28924.851128] option 1-1.3.2:1.1: device disconnected
' [7 G5 @: ^% K[28924.851505] option1 ttyUSB2: GSM modem (1-port) converter now disconnected from ttyUSB2
[28924.851594] option 1-1.3.2:1.2: device disconnected
[28924.851922] option1 ttyUSB3: GSM modem (1-port) converter now disconnected from ttyUSB3
[28924.852071] option 1-1.3.2:1.3: device disconnected
3 S6 b4 H5 V2 Q# h[28924.852471] option1 ttyUSB4: GSM modem (1-port) converter now disconnected from ttyUSB4
& {4 E' ~) G/ r3 G3 R2 T% S' |[28924.852564] option 1-1.3.2:1.4: device disconnected
- u+ x) {" A+ F/ {7 ]8 D, V[28924.947089] usb 1-1.3.2: reset full-speed USB device number 6 using dwc_otg
[28925.027054] usb 1-1.3.2: device descriptor read/64, error -32
[28925.158316] usb 1-1.3.2: USB disconnect, device number 6
+ X0 S/ M; Z% U4 y* s. d( ]: L& e[28925.470122] usb 1-1.3.2: new full-speed USB device number 9 using dwc_otg
3 q7 [" p$ p1 L, w7 P[28925.592934] usb 1-1.3.2: New USB device found, idVendor=19d2, idProduct=0152
! Q: B" V* Z- r4 [[28925.592966] usb 1-1.3.2: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[28925.592984] usb 1-1.3.2: Product: ZTE CDMA Technologies MSM
[28925.592999] usb 1-1.3.2: Manufacturer: ZTE, Incorporated
[28925.600518] option 1-1.3.2:1.0: GSM modem (1-port) converter detected
[28925.601158] usb 1-1.3.2: GSM modem (1-port) converter now attached to ttyUSB0
6 U, q1 _7 p' f! P) }[28925.603503] option 1-1.3.2:1.1: GSM modem (1-port) converter detected
  H( Q9 [" A9 x( e# `% H[28925.603999] usb 1-1.3.2: GSM modem (1-port) converter now attached to ttyUSB1

在掉线以后再用wvdial 3g拨号则会出现如下情况：
--> WvDial: Internet dialer version 1.61
--> Initializing modem.
--> Sending: ATZ
+ d3 w; H' [! i" ^7 I! E6 O3 i--> Sending: ATQ0
--> Re-Sending: ATZ
" T* o. O# h) V. Y--> Modem not responding.
/ W8 h7 Z( h# W9 _/ z1 e无法拨号

拔掉3g上网卡再重新插上，重新拨号又可以正常上网，求教一下3g上网卡掉线提示是什么意思，该如何解决。
本人刚入论坛不久没法给出多余金币望见谅。

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