NEXEDGE™ is Kenwood's Digital PMR range of portable, mobile and repeater radios. NEXEDGE™ extends the life of current radio system assets, because all NXDN™ digital modes use the same Class-C power amplifiers and site management equipment used for current analogue stations, ensuring return on investment (ROI) and a multitude of supplier choices. Current analogue and NXDN™ digital fleets can share a NEXEDGE™ base/repeater station in 12.5 kHz conventional "Mixed Mode," thus providing uninterrupted service as long as needed and a straightforward migration path as aging analogue fleets are replaced with digital. Also, NEXEDGE™ trunked traffic channels can be shared with existing external analogue conventional or LTR® trunked logic controllers, extending service to fleets while a transition to NXDN™ trunking is underway.
AMBE+2™ Vocoder. This is a state-of-the-art voice compression digitization technology offering superior clarity at varying signal strengths, even at highway speeds. It's at the heart of Kentwood’s NEXEDGE Digital PMR radios introduced in early 2009. The AMBE+2 Vocoder digitizes speech while retaining natural voice nuances, performs noise reduction, introduces FEC and compresses this voice data to accommodate land mobile radio data rates. Next the radios digital signal processor (DSP) protocol- packages the Vocoder, signalling, control, and more FEC data together and converts this to a uniquely filtered 4-Level FSK digital waveform that modulates the transmitter. This results in an industry superior low bit-error-rate digital air interface delivering robust communications even in weak signal strength areas. The NXDN™ air interface is capable of fitting into both narrow 12.5 kHz and very narrow 6.25 kHz bandwidth channels meeting the tightest of spectrum efficiency requirements (9600 bps @ 8.3 kHz and 4800 bps @ 4 kHz occupied bandwidth respectively).
NXDN™ is a Frequency Division Multiple Access (FDMA) methodology whereby one user accesses a channel frequency at any one point in time (i.e. accesses via the frequency domain). Other digital methods such as Time Division Multiple Access (TDMA) permit more than one user to access the channel frequency via timeslots (i.e. accesses via the time domain), but there has to be a tradeoff between coverage and effective transmission rate, as increasing the former means decreasing the latter. Kenwood's NEXEDGE™ systems support the following NXDN™ digital modes, Digital Conventional/Digital Trunked/Digital Trunked Wide Area IP Networks - in addition, all NEXEDGE™ equipment can support legacy analogue modes.
Dual-band Amateur Radio transceivers operate on the VHF and UHF bands. The radios have a single high-spec antenna port and their internal filter circuitry passes the signal to both band sections simultaneously. Separate volume and squelch controls for each band means the operator can monitor two frequencies at the same time, even if both are on the same band.
Electronic Serial Number (ESN)
Portable, mobile and repeater Business/PMR radios have their serial number stored
internally in an electronic format as an added identification and security feature.
This ESN cannot be changed or deleted and can be used to identify the owner of a
particular radio even if the printed serial number plate on the radio body has been
lost or tampered with.
Is a world-wide VoIP/Amateur Radio network. The TM-V71E and the TM-D710E mobile
transceivers have dedicated functions, ports, connector cable sets and free software to
make operating this mode as simple as possible.
FleetSync & FleetSync II.
These are digital electronic signalling systems built-in to some of our high-end two-way Business radios which offer digital fleet unit identification, selective calling, status messaging and text messaging for dispatch operations. Every time the radio transmits, it sends out its identity in a digital format (this is known as PTT ID) - it is transmitting a digitally coded identity number (known as digital ANI) for instant identification of each call. The radios can also transmit a special Emergency code to highlight that an operator may have a problem. Selective calling means that each radio on the system can be called individually, since each has its own electronic identity code. Depending on which radio model is in use, short/long text messages can be transmitted and received.
Internet Voice-over-IP operation.
The TS-480HX and TS-480SAT Amateur Radio transceivers can be controlled remotely via the Internet. In addition they can transfer both Receive and Transmit audio via VoIP for fully remote operation. “Remote” could be via Wi-Fi from your garden to the room where the radio is installed, or it could be around the world on a broadband connection.
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This is one of a range of international standards that define the resistance of a product to various environmental hazards.
IP stands for “Ingress Protection” and the IP-55 standard covers dust as well as low pressure water jets from any direction (often known as “driving rain” protection).
Kenwood radio products carrying the IP-55 rating are therefore built to this high standard of protection against the sort of factors found in normal use.
Electrotechnical standards are harmonized around the world by the International Organization for Standardization (ISO).
Amongst its primary internationally recognised standards is ISO 9001, for Quality Management.
Kenwood Communications Equipment Division is certified under ISO-9001 by UKAS (United Kingdom Accreditation Service) and also by the Japan Quality Assurance Organization (JQA).
This is a group of standards issued by the American Dept of Defence.
Originally conceived to regulate quality control and fitness-for-purpose of items used by the American military, it is now also widely applied to civilian products because it’s recognised world-wide.
There are many individual factors that can be assessed – Kenwood is mainly concerned with MIL-STD’s environmental standards such as temperature/temperature shock, salt fog, vibration, rain etc. (we haven’t yet tried the “Gunfire Vibration” test!).
QT, DTMF and 5-tone.
Before FleetSync digital signalling was invented, radios used several different analogue signalling systems based on audio tones. Different systems used different numbers of audio tones, in combination or singly, but they were all intended to add extra functions to the basic operation of the radio. They could switch on the receiver if they heard a pre-set tone from another radio, so that both stations could make contact. On more complex multi-radio systems these tone combinations helped manage the radio traffic on the channel. 5-tone signalling was the most sophisticated and can now be used in combination with digital FleetSync for short/long text messaging (via suitably equipped radios). Even today analogue signalling is an important function for many users and our radios continue to provide all the current formats.
Remote Head Unit
This feature enables a mobile radio transceiver to be more easily installed in a vehicle, or mounted in a base-station, by separating the control head from the main body.
The two parts are connected together by a control cable; the microphone, antenna and accessory cables then plug in to the head or the body as appropriate.
Some Kenwood transceivers are designed to have a permanently detached head, others are supplied as standard with the head clipped on to the body but with optional “remote mounting” kits available.
TX/RX AF DSP.
16-bit Digital Signal Processing is implemented at audio-frequency to handle noise reduction, equalizers and audio filters.
Voice Inversion Scrambler.
Found in many of our Business two-way radios, this function scrambles the operator’s voice before transmitting it so that it is incomprehensible to normal casual eavesdropping. The radio that is receiving the scrambled signal is pre-set with a matching code to unscramble it, converting it back into normal speech for the listening operator.
"VOX" actually means "Voice Operated Transmit" - it's a function found in both our Professional and Amateur radios, specifically the portable ones. The VOX circuitry inside the radio listens for sounds coming from the microphone that are louder than a pre-set level - when it hears these it switches the radio to transmit until the sounds stop. In practice this means that the operator can simply talk whenever they want to, without having the radio in their hand (or needing to push the transmit button on a speaker/mic unit). Obviously you wouldn't want background noises to trigger transmission, so the correct threshold level can always be adjusted by the operator. A "VOX" headset will have its microphone connected directly to the radio with no Push-To-Talk switch in the way, so it's "live" all the time and the radio's VOX circuitry is always on alert.