The major new product on show from Tait Communications at Critical Communications World 2015 was its UnifyVoice solution, which enables users to seamlessly communicate over any available LMR, cellular or Wi-Fi network.
UnifyVoice enables more effective and efficient communications by integrating and providing the benefits of both push-to-talk (PTT) over cellular and LMR (land mobile radio). This enables end users in the office or out in the field to benefit from seamless mobile communications.
Jamie Bishop, marketing manager for EMEA region at Tait, told Wireless: ‘Mobile phone or tablet users just need to download a PTT app - both Android and iOS versions are available.’ He added that it is also available for secure Android, so it can be used on ruggedized Android devices too.
‘To set up a PTT call between smartphones you just click on a person’s name (or call group) and the PTT operates. The PTT application also supports the capability to map the users’ location, so as an alternative you can see a colleague’s location on a map and by clicking on their icon it opens the PTT call. You can also programme an external function key on the phone to act as a PTT button,’ explained Bishop.
The UnifyVoice unit on display at CCW is a base station (which would normally be housed in a rack) with a router to provide a wireless connection to the internet (or more normally a fixed connection to the internet). It has a gateway inside which interconnects a DMR or P25 network to the PTToC network, allowing the call from the smartphone to be transmitted over the 3G or 4G network to the PTToC server, and then passed back to the base station to reach the two-way radio terminal.
A key innovation within Tait UnifyVoice is the remote SmartMicrophone (pictured below), which provides LMR users with a familiar interface, and all they need to do is push the PTT and talk as the system automatically determines what network is available. The SmartMicrophone is tethered to the LMR radio and connects by Bluetooth wireless to a smartphone to obtain cellular or Wi-Fi network access. Using the PTT button on the IP67 certified mic, the user can talk over the narrowband system to another two-way radio – or he can talk via the PTT server to a smartphone.
Where this is particular useful is when the radio user with the connected hand mic goes outside of the DMR radio area he gets coverage extension on cellular via the Bluetooth connection between the mic and the smartphone. The call hands over to the cellular system seamlessly without dropping.
In short, the two-way radio terminal roams onto the cellular network, which is very handy when the users moves beyond the private DMR coverage area or goes inside a building where public cellular coverage, or Wi-Fi, is available.
‘The other difference to just having a normal mic is that encryption is maintained between LMR radios irrespective of whether the call is carried via the LMR, cellular or Wi-Fi network. Also calls within the PTToC system are also AES encrypted. So, if it is a call between a two-way radio and smartphones, the call remains encrypted throughout the LMR network, is unencrypted at the gateway and then re-encrypted using AES to travel through the PTToc system to the Smartphones,’ explained Bishop.
‘UnifyVoice is very useful in places like airport where there are two or more networks, or where you only have two channels available,’ he continued. ‘You can send most private calls over the cellular or Wi-Fi system and reserve the LMR system for higher priority radio to radio communications.’
Bishop added that it is the middleware in the radio that decides what bearer is used at what time, as this is completely customisable through policy settings.
He also said that Tait’s ATEX DMR radio should be available in September, as it is in certification testing now. Its TP9310 analogue conventional/DMR Tier 2 entry level hand portable is due out in July. It has no display or keypad and comes with a simplified interface. It will be available in Tait’s full colour range.