Digital Two Way Radio?
DPMR DMR Digital mobile radio
digital private mobile radio
DPMR push to talk 400-480mhz UHF NFC rugged phone 2G RAM New factory 5INCH Phone!! 5inch Original NFC Mobile Phone IP68 Waterproof DPMR Walkie talk.
What is the difference between DMR and dPMR
A little explanation about DMR and dPMR standards may be of interest.
To reduce the congestion present in today's crowded radio spectrum, radio channels must be used more efficiently.
The basic idea is to divide existing radio channels in half, thus doubling the number of channels available.
The term "frequency" which most people are aware of, is actually only a spot centre frequency in the middle of a small band of radio spectrum (a channel).
Before.
After.
Historically, this "dividing" has happened a number of times over the years. As analogue radio technology improved, existing channel widths were cut in half.
Unfortunately, there came a point when it seemed that this technique could no longer be used.
Many were of the opinion that the physical limits of analogue filtering technology had reached a plateau and was not capable of narrower channel widths.
Some manufacturers, however, were of the opinion that a combination of digital and traditional analogue techniques made physical channel division a viable proposition.
So, there have been effectively two technologies researched and developed alongside each other.
The dPMR standard which relies on FDMA (Frequency Division) techniques, which relies on the old analogue way of physically dividing an existing channel.
And the DMR standard relies on TDMA (Time Division) techniques, which relies on creating two 2 "virtual" channels within a single existing channel by transmitting information in "time slots".
Of the two technologies, the dPMR was (theoretically) technically easier to implement, making it the cheaper option.
Even now, the two camps are using various "marketing" press releases and other documents to extol the virtues of their own technology.
Each time advantages / disadvantages are highlighted by one side, advances in technology renders their arguments null and void.
It seems that because both technologies are still in their infancy and are constantly evolving and improving, the argument about which standard is "the best" will not be settled anytime soon.
Want to know more about two way radio?
A little explanation about DMR and dPMR standards may be of interest.
PMR446
From Wikipedia, the free encyclopediaMotorola TA288 PMR446 licence free radio.
PMR446 (personal mobile radio, 446 MHz) is a part of the UHF radio frequency range that is open without licensing for business and personal use in most countries of the European Union. (It has roughly the same use asFRS or GMRS in the United States and Canada.) Depending on surrounding terrain range can vary from a few hundred metres (in a city) to a few kilometres (flat countryside) to many kilometres from high ground. It is ideal for small-site, same-building and line of sight outdoor activities. PMR446 is used in both professional and consumer-grade walkie-talkies (similar to those used for FRS/GMRS in the United States and Canada).
Historically, analogue FM is used but a digital voice mode has been available in radios conforming to digital private mobile radio (dPMR446) and digital mobile radio (DMR Tier 1) standards designed by ETSI.
The Human Factor – Protect and Strengthen Your LMR System
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Spare Two Way Radios: Are They A Bad Idea?
Are service spares for your two way radio system a bad idea?
After all, spare two way radios would reduce downtime whilst faulty radios are away for repair.
The idea of having spare two way radios to cover faulty downtime sounds appealing, but spare two way radios can also create bigger problems than having no spares at all.
We have clients who have spare radios for their system.
Some have deliberately purchased spare radios, whilst others have acquired spares from reorganisation or staff leaving.
· Conventional Analog
· Digital Radio
· DMR
· LTE
· Mining
· News
· P25
· Podcasts
· Public Safety
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