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satellite nyc Antenna-Theory.com Newbie
Joined: 30 Jun 2016 Posts: 2
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Posted: Thu Jun 30, 2016 4:21 pm Post subject: LTE Hotspot External Antenna |
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Hi Folks,
New to the forum and hope to be of help with anything satellite related. I am honored to be a part of this forum after my review of many of the posts and hope to carry my own weight.
Question: I have an argument going on with a person about external LTE modem antennas. My case is the FCC does not allow any antenna on any intentional radiator that the manufacturer has not pre-approved after testing for compliance with FCC specs.
Other persons argument if the tower controls the TX output of the LTE modem so you can use any antenna you want.
Silly argument on their part because how do they know what tower they are hitting if they are radiating 10 watts? How do they know they are staying in even close to in band?
Finding the regs for this for unlicensed bands like ISM was easy. Cellular regs not as easy. I have looked and looked.
Any advise or direction on this would be appreciated.
Bruce W. |
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admin Site Admin
Joined: 03 Jan 2007 Posts: 247
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Posted: Thu Jun 30, 2016 5:31 pm Post subject: |
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Yeah, so the tower only knows the received signal at it's end, it doesn't know what the peak gain is for the actual user equipment. However, the tower can only request max power from the chipset, which for cellular's case (3g/4g/lte) is limited to about 24 dBm (250 mW).
The phone/modem itself is certified by the FCC (it doesn't radiate out of band, it passes SAR, peak gain, etc). So yeah you could definitely hook up a super high gain antenna to a radio in your modem or phone and have it fail FCC specs.
Your comment on "staying even close to in band", that isn't a function of hte antenna. The radio sits on predetermined channel (frequency) and the antenna itself won't have any impact on that, that's all set by the logic in the radio. |
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satellite nyc Antenna-Theory.com Newbie
Joined: 30 Jun 2016 Posts: 2
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Posted: Thu Jun 30, 2016 5:44 pm Post subject: |
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Admin,
Wow I got the Admin first post. Nice. Thank you.
What I meant by Out of Band was more a function of how the specific antenna was tuned which affect the oscillation frequency. The antenna itself, if not a correct one, would in essence re-tune the frequency. Wrong?
Any chance you know where I could find any regulation on external antennas for LTE within the FCC? They have hidden them in lots and lots of words.
Thank you again.
Bruce |
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coundpake Antenna Theory Regular
Joined: 03 Aug 2016 Posts: 10 Location: San Jose, CA
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Posted: Wed Aug 03, 2016 8:45 pm Post subject: |
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| Quote: | | What I meant by Out of Band was more a function of how the specific antenna was tuned which affect the oscillation frequency. The antenna itself, if not a correct one, would in essence re-tune the frequency. Wrong? |
The frequency is not a function of the antenna. Antennas might work better for some frequencies than others but the frequency of transmission is decided by the radio chipset. |
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