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Do somebody knows what´s the recommended heigh to install an access point 1242 with external antennas 1728 on a flat area?

Do somebody knows what´s the recommended heigh to install an access point 1242 with external antennas  1728 on a flat area?
And for example, if i use aps 3602 the heigh to install is the same??
 
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  • Getting Started with Wireless
8 REPLIES
Hall of Fame Super Gold

That antenna is a multi-point

That antenna is a multi-point antenna suitable for wireless bridge.   It is not designed to service wireless clients.


Exactly, what are you trying to do with this?

Imagine a very big flat space

Imagine a very big flat space like cisco live, we have some aps 1242 with those kind of antennas that are omnidirectional, I´ve seen in some cisco documents that the maximum heigh to install an AP is 6 mts to 8mts but with this antennas we have more gain, and that´s my dude, if there´s a specific maximum heigh to install an ap with internal or external antenna. THANK YOU.

 

REGARDS

Hall of Fame Super Gold

Imagine a very big flat space

Imagine a very big flat space like cisco live, we have some aps 1242 with those kind of antennas that are omnidirectional

Depends on the dimension of the space ... one thing you need to consider is this:  The antenna is a high-gain antenna.  So this means at the outer fringes of the range, the client can hear the AP.  Your problem will be this:  How can the AP hear the client if the client has a low-gain antenna?  The AP can't.

 

Hence, this antenna is designed primarily for multi-point wireless bridge deployment.

Bronze

Hi,If you are talking about

Hi,

If you are talking about AP 1242 high then you can install it in same high as 3602 but
As antenna 1728 is designed primarily for outdoor multi-point wireless bridge deployement,
so it is better you install the AP 1242 near the Antenna 1728, to avoid the losses cause by cable length.

As you have mention you are using this antenna in flat area means no buildings, no hurdles, clear view in that case you can install this antenna on roof top at normal view able high to wireless bridge clients.

For example, in a cisco ccnp

For example, in a cisco ccnp wireless study guide I saw that the recommended heigh to install a CISCO AP is 6 to 8 mts, in this case using that kind of antenna is the same or I can install the AP higher?, the roof is approximately 16 mts. REGARDS
Cisco Employee

Based on both line-of-sight

Based on both line-of-sight and Fresnel zone requirements, Table 3 provides a guideline on height requirements for 2.4-GHz antennas as various distances. This refers to height above any obstacles located in the middle of the RF path.

Table 3. Guideline on Height Requirements for 2.4-GHz Antennas

Wireless Link Distance (miles)

Approx. Value “F” (60%Fresnel Zone) Ft. at 2.4 GHz

Approx. Value “C” (Earth Curvature)

Value “H” (mounting Ht.) Ft. with No Obstructions

1

10

3

13

5

30

5

35

10

44

13

57

15

55

28

83

20

65

50

115

25

72

78

150

A 10-dB fade margin is included for 2.4-GHz calculations, while the included 5-dB fade margin for5-

To determine the required

To determine the required height of an antenna tower over a hypothetically flat, spherical Earth, it's necessary to calculate the effect of the Earth's curvature, and then add a distance equal to 60% of the radius of the First Fresnel Zone. The table below shows the result of these calculations. Values have been rounded up to the nearest foot.

It can be seen in the table above that a wireless link between two points separated by 26 miles would require an antenna tower with a minimum height of 103 feet for an 802.11b/g radio and 95 feet for an 802.11a radio. In practice the heights would typically be 20 feet higher, or more. This is because the Earth is not smooth and flat and the tower height must be raised to compensate for buildings, trees, hills, or other obstacles. For example, in a suburban setting, with houses and small offices, it may be necessary to add 20 to 40 feet to the tower height to get over the homes, offices, and trees that would be in the line-of-sight between the two towers.

At this moment I can say that

At this moment I can say that one of the AP with 1728 antenna is 20 mts of heigh aprox, is that good ??

do we have to take down the ap to give better services taking about the flat area????

 

REGARDS

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