Cisco Cisco WT2750 Multipoint Broadband Wireless System Guia De Informação
Q. What is non−line−of−sight transmission?
A. The coverage range of non−line−of−sight transmission depends on these parameters:
Path loss assumptionHow much signal is lost along the transmission path.
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Link reliability and availability requirementHow many 9s service providers must
guarantee over the wireless link.
guarantee over the wireless link.
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Customer premises equipment (CPE) ODU transmission powerStandard power
ODU or high power ODU at the CPE end.
ODU or high power ODU at the CPE end.
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Antenna gainThe type of antenna used at the CPE end.
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Channelization and performance requirementWhat type of channelization and
performance required for each sector.
performance required for each sector.
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Number of receiving antennaeOne or two.
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With a standard power ODU with high gain antenna, the WT−2750 Multipoint Broadband
Wireless System can achieve six miles in non−Loss of Signal (LOS) transmission with two
antennae/ODUs for each CPE, and three miles with a single antenna/ODU, when it meets
99.9% link availability requirement, and uses 6 MHz channel downstream, and 3 MHz
channel upstream for each sector at normal path loss.
Wireless System can achieve six miles in non−Loss of Signal (LOS) transmission with two
antennae/ODUs for each CPE, and three miles with a single antenna/ODU, when it meets
99.9% link availability requirement, and uses 6 MHz channel downstream, and 3 MHz
channel upstream for each sector at normal path loss.
Q. What are the intermediate frequency (Ifs) for the Headend (HE) and
Subscriber Unit (SU)?
Subscriber Unit (SU)?
HE: 324 MHz TX, 420 MHz RX
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CPE: 330 MHz TX, 426 MHz RX
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Q. What Cisco IOS® releases currently support the Multipoint Broadband
Wireless System?
Wireless System?
12.1(3)XQ1
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12.1(3)XQ2
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12.1(5)XM
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12.2(1)T (available February/March 2001)
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Associated microcode
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Q. What downstream frequency bandwidths are allowed? Can I change
this?
this?
A. Bandwidths of 6 MHz, 3 MHz, 1.5 MHz are allowed. The HE line card is configured to
use a single channel 6 MHz wide, unless there are Radio Frequency (RF) variables that do not
allow this configuration.
use a single channel 6 MHz wide, unless there are Radio Frequency (RF) variables that do not
allow this configuration.
Q. What are the different upstream frequency bandwidths that I can
configure?
configure?
A. The bandwidths are 6 MHz, 3 MHz, and 1.5 MHz. Because subchannelization is possible,
you can use combinations of each of these channelization schemes. For example, if you use
three upstream ports, you can have one upstream set for 3 MHz and the other two set for 1.5
MHz. You cannot exceed 6 MHz total with these combinations.
you can use combinations of each of these channelization schemes. For example, if you use
three upstream ports, you can have one upstream set for 3 MHz and the other two set for 1.5
MHz. You cannot exceed 6 MHz total with these combinations.