During a session at the BAPCO Annual Conference and Exhibition, Dr Yong Chang, vice president, government and enterprise solutions at Samsung Electronics said that the company is partnering to investigate the potential for a remote speaker microphone (RSM) device with TETRA radio functionality [both trunked mode operation (TMO) and direct mode operation (DMO)].

The device is currently at the proof of concept stage and Samsung is in discussions with the Home Office regarding it and is also gathering end-user requirements (it was actively doing during the show on its stand). The device is being developed in collaboration with a TETRA technology partner.

Iain Ivory, founding partner at consultancy Hermitage Comms, highlighted the need for this product to be delivered at an acceptable price point to the market, saying that this will be key to its adoption by end-users. He explained that while in some countries migration from PMR to LTE for public safety is expected to take a number of years, which creates a need for a long-term capability for TETRA-LTE interoperability, which the market is addressing with hybrid TETRA/LTE devices such as the Tactilon Dabat from Airbus, “That’s not the case with ESN, it’s a blunt migration... So in the UK market the only [hybrid] niche is the device-to-device (D2D) requirement. And if it’s D2D, then it has to be at a low price point as low usage, low functionality. If it’s a long migration than you can justify a higher price point."

ProSe is enabled on at the hardware level on Samsung’s new ESN ruggedised handset and as previously mentioned, Samsung is working to address the issue of ProSe’s limited range (compared with PMR radio’s back-to-back mode). However, Ivory notes that there is limited scope for boosting ProSe’s transmission power to address this issue, given the potential regulation issues and the need to avoid impacting on adjacent systems. “Even if they increased the range of ProSe so that the D2D range was equivalent to a [PMR] radio, when you look at use cases for DMO in the worldwide market, DMO repeater or DMO gateway are the main worldwide use cases (excluding the UK). As neither functionality is supported in ProSe, I believe there needs to be an alternative solution.”

On the Samsung stand, I got to see a proof of concept in-vehicle solution – a collaboration between Sonic Communications, Nextivity and Strike – which is designed to enable Samsung's public safety LTE devices to be used in an in-vehicle context – “Type I” (shown below). It consists of an in-cab cradle for a public safety LTE handheld device, which would be allocated to the vehicle, as in practice it would be cumbersome for a police officer to have to detach the one they’ve been issued with from their personal protective equipment (PPE), before they have access to in-vehicle communications. The cradle and associated cabling and equipment connects the cradle to an external roof-mounted antenna with multiple antenna elements. The user interface consists of a passenger side telephony style corded handset, driver side PTT button and a simple control panel with +/- channel and volume buttons.

Author: Sam Fenwick