Richard Martin explores the latest TETRA handsets and the technologies their manufacturers have used to increase the handsets’ usability and resilience, while also adding new features and paving the way for combined use of TETRA and LTE
TETRA manufacturers have not been idle over the past few months, with many embracing the use of LTE for high bandwidth data and this will be clearly seen at this year’s CCW in Amsterdam. Manufacturers have also updated their radios to offer other new features. With this in mind, now is a good time to review the latest portable TETRA offerings from the five main manufacturers.
Stephen Harris has years of experience in radio hardware design as a senior engineer at Motorola Solutions and Cisco. He says the size of the consumer cellular market is the major driver for reducing costs, increasing functionality, and reducing power consumption and size.
The latest smartphone radio transceivers combine almost the entire RF system, and are starting to include other RF systems such as GPS. But the transmitter power amplifier is still a separate device.
Sub-systems such as cameras, Wi-Fi, Bluetooth, and accelerometers are available as self-contained integrated circuits or modules typically only 3mm to 5mm per side. These can be used to enable numerous applications. Ideally the major systems on chip would connect together without needing ‘glue’ parts, but in practice this is not often achieved. However, advances are still being made in ‘glue’ ICs, many of which are now no larger than passive parts.
One important area that has so far resisted being infiltrated by silicon is tuneable RF filtering. A low cost, small size, low power tuneable filter is the Holy Grail, and would enable truly software-defined radio.
Peter Hudson, head of technology and innovation at Sepura, says that it is has always been a challenge to access the latest technology and apply it to low volume products and markets such as TETRA. The lifespan of new technology is often too short for TETRA users, who expect products to be supported for 10 years or more. However, the increased use of microprocessors in automotive and machine-to-machine applications has opened up access to these technologies in the quantities required for TETRA manufacturers.
The use of mainstream operating systems such as Linux, enable faster development cycles and innovative product solutions. Custom integrated circuits are still used to cater for requirements that cannot be met with commercially-available components, but this has the benefit of improved power efficiency. Digital signal processing can achieve less drop-off in wideband systems and more accurate intermediate frequencies.
Battery life, display and sound
Power management is a key concern for manufacturers as users have ever more demanding usage requirements. This challenge is compounded with the addition of features such as Wi-Fi. Hudson says that battery technology goes in leaps and bounds, and is currently in-between innovations.
Display technology continues to evolve at a rapid pace driven by smartphones. Screen sizes and resolution have increased so that more information can be clearly displayed.
As radios become capable of receiving images and possibly video clips in the future the capability of displays becomes more important.
Antenna technology has changed slowly but good results can be had if handset and antenna manufacturers work together to achieve a good match, and particularly take into account the use cases of the product and antenna together when designing a solution.
Airbus Defence and Space’s Secure Communications division believes that public mobile radio developments such as smartphones will drive trends in TETRA handsets, especially as LTE has increasingly been playing an important role in mission-critical communications. Future developments for TETRA and Tetrapol handsets will be affected by smart devices and their applications and user interfaces.
Future developments
Application ecosystems such as Android will change capabilities without needing long development projects. To operate most efficiently with limited resources streamlined working methods and tools are necessary. Broadband mobile devices with applications based on open standards will enable this provided that security is included in the design.
Integrating different technologies will optimise terminals’ size, making future products lighter and more usable in the field. For example, police officers who are used to carrying many gadgets will see several of these integrated into
smart devices.
PMR devices as life-saving tools must provide voice service at any time. Demanding security requirements set limitations for terminals’ minimum size and their design. However, the latest TETRA and Tetrapol products are getting smaller. Airbus believes that for the foreseeable future it will be essential to use existing TETRA and Tetrapol technology for mission-critical voice, because of its unique user-friendly handling, security features and availability.
Bluetooth and other wireless connection technologies connect sensors and peripherals that are able to support
various multimedia formats, such as voice, data, picture and video. Some picture applications such as facial- and licence plate-recognition have already been incorporated into
PMR technology.
Increasingly touchscreens will be the prime interface for radio users. Other aspects that PMR radios of the next generation will be offering include evidence collection and data management, dynamic mapping services, collaboration with citizens, office applications, broadband data, better voice technology, and batteries of higher quality and durability.
Now that we have explored the design features of current handsets, and what might be yet to come, let’s take a
closer look at the latest portable radios from the five
main manufacturers.
Motorola Solutions
Motorola Solutions has launched the MTP3000 series and the MTP6000 (pictured left) over the last few years, both based on a new technology platform that takes advantage of more powerful processors and larger memory. With the MTP3000 Motorola Solutions used a two control knob format to make the devices easy to operate for those upgrading from analogue radios. Transmission power has been increased with the option of class 3L (1.8W) where this is permitted.
The MTP3000 series has recently been expanded with the addition of the MTP3500 and MTP3550, which have end-to-end encryption, vibrate alert and man-down capability. Bluetooth 2.1 is supported on all of the radios, offering enhanced security during pairing and operation compared to Bluetooth 2.0. All of these radios and their bigger brother the MTP6000 series incorporate the Slimport audio system ensuring excellent audio clarity while meeting IP67 environmental specifications. Audio power has been increased to 2W to punch through the background noise typically found in street or industrial environments.
Audio accessories such as remote speaker microphones are also available.
The MTP6000 series shares all of the features of the MTP3000 but with a larger and higher resolution screen and a single control knob for talk group and volume. The MTP6750, the top of the MPT6000 series, includes a five megapixel digital camera, complemented with a back-office application – Photograph and Intelligence Communications System (PICS) – that stores images securely with a digital fingerprint so they cannot then be changed.
Motorola Solutions also offers integrated Terminal Management (iTM) to remotely upgrade and reprogram a fleet of up to 150,000 radios from a central location.
Leonardo-Finmeccanica
Italian firm Leonardo-Finmeccanica is renewing its handheld offer with the new PUMA T4 family, introducing a new concept in TETRA by joining the versatility and functionality of a smartphone with the robustness and reliability of a TETRA radio. The new device guarantees the traditional capabilities in term of push-to-talk and supplementary services on a handheld terminal that has a touchscreen interface and open operating system. The Puma T4 family features innovative design and construction separating GUI and computing from communications: a ruggedised Android-based smartphone core provides computing, ancillaries and MMI functions are matched with modem component providing the main connectivity option. Different modems enable the Puma T4 to be deployed in TETRA, LTE, or dual mode TETRA-LTE. All components are available in a rugged IP67 enclosure.
The Communications Service Platform (CSP) is the Leonardo-Finmeccanica infrastructure that provides multimedia services. It is used to run voice over LTE (as a pre-standards version of Mission-Critical Push to Talk) and to provide integration between TETRA and LTE. Multimedia can be exploited even when the available radio carrier does not provide broadband capability; recording features such as local SD storage allow capture of video and pictures that can be uploaded via Wi-Fi once the user is back at their office, or over suitable and trusted coverage.
In addition Leonardo-Finmeccanica is embedding its Optical Character Recognition capabilities in the device, transforming the Puma T4 into a portable license plate reader capable of matching scanned plates against a list of suspect vehicles. This basic capability can be enhanced using the Puma T4 cradle to make the terminal into a transportable mobile checkpoint able to scan documents, conduct biometric (fingerprint) checks, and undertake night operations supported by an infrared illuminator.
Airbus Defence and Space
Airbus Defence and Space is presenting its TETRA-LTE integrated handset, the Tactilon Dabat (pictured left), at this year’s Critical Communications World. The device consists of a fully rugged (IP67-rated) smartphone with an inbuilt TETRA radio. It offers the multipurpose buttons of Airbus Defence and Space’s other TETRA terminals, such as the emergency and push-to-talk buttons and the device’s audio processing is designed for professional use, enabling loud and clear communication.
The large 4.7inch touchscreen can be used while wearing gloves and the Tactilon Dabat’s TETRA module offers all the functionalities found in TETRA radios. The device has front and back cameras and images captured with them can be shared with TETRA group in a controlled and safe manner. The device can also be worn on the label to capture videos and then send them onto a control centre or to colleagues.
The TH1N offers the advantages and connectivity of TETRA, but in a more compact and easily concealed or carried handset. In spite of its size the unit is fully featured and highly ruggedised. Thanks to its compactness and dedicated range of accessories this terminal is well-suited for covert operations. Dust and water resistant to IP65/67, it has a 1.8W RF power option with standard and extended batteries for different operator endurance requirements.
Airbus’ latest generation TETRA radio, the TH9, is primarily for public safety but is equally suitable for industrial use as it is IP65-rated. RF power is available at 1.8W when permitted. A new audio design makes it possible to hear callers clearly whether in receiving or transmission mode. The radios are fitted with receivers for GPS, GLONASS, BeiDou, and Galileo navigation, any two of which can be used simultaneously for fast and highly accurate location. New connector designs increase ruggedness, and Bluetooth can link accessories wirelessly. The TH9 comes with a wide range of audio accessories, a car kit with an automatic connection to an external antenna, and
two battery options. The high capacity battery offers 4600 mAh performance.
The Taqto terminal management tool enables multiple radios to be updated and reconfigured simultaneously over the IP network.
Hytera
Hytera’s Z1p (pictured right) follows the trend for smaller units, but is fully-featured and comes in a tough metallic case rated at IP67. At 270g and only 23mm thick it can be easily carried, and a range of accessories make it highly adaptable. These accessories can be linked with the integrated Bluetooth wireless module, leaving the user’s hands free.
The PT580H Plus is a more conventional form factor radio, again rated at IP67. It includes a DMO repeater Type 1A to boost the range, and audio is improved with noise cancelling. A variety of accessories are available and the radio is equipped with Bluetooth for use with wireless accessories. A two-colour push to talk button is provided, and a labelling area for user identification.
Both radios use the two control knob format (these are of different sizes to make it easy for the user to know whether they are changing channel or volume). Both radios can transmit at 3W (Class 3), while the two-way communication of TETRA Trunked Mode Operation (TMO) is based on a balanced link. Particularly in Direct Mode Operation (DMO) the use of 3W transmit power is expected to provide longer ranges. It should be noted that in some countries these higher powers are not permitted for user safety reasons.
Sepura
Sepura supplies TETRA hand portable radios, offering extensive functionality and coverage with up to 3W of RF power. Providing excellent water and dust resistance – together with ATEX/IECEx intrinsically safe options – ‘tough technology’ allows them to function in arduous conditions.
STP9000 series
The STP9200 has 1W audio, long battery life, 1.8W TETRA RF (Class 3L), a sunlight-visible display and safety-enhancing features such as man down, GPS, and wake-on-alarm. The radio is IP67-rated and marine hardened/salt resistant, continuing to work after submersion in up to one metre of water for up to 30 minutes. Usability is enhanced with smart menus, programmable softkeys, selectable menu style (grid/list/tab) and a rugged accessory connector. The STP9200 features the Sepura SDA applications environment, allowing custom applications to be added by end users. This can also link through to back-office applications enabling easy querying of information directly from a radio.
All Sepura hand portable radios can be used as a TETRA repeater while simultaneously working as a radio for the
end user.
The STP9000 and STP9100 are mid-tier products and include all the features of the STP9200, but introduce a colour high-resolution display and full or reduced keypads designed for gloved use. Additional functionality includes integrated indoor positioning capability, man down, GPS, Bluetooth, WAP, and SDS with embedded URL shortcuts. Picture messaging allows images to be sent to a group of TETRA radios. The radios have micro SD local storage, and the hosting of local WAP sites provides information such as Hazmat or work instructions that the user can refer to on the move.
SC20 series
These broadband-ready TETRA hybrid radios combine the mission-critical security and advanced performance of TETRA with an optional high-speed second data bearer. Dustproof and waterproof IP66/67/68-certified, the SC20 series’ ergonomic non-slip case is impervious to water and continuous immersion to a depth of two metres for one hour.
The SC20 has a class 3 high-power RF transmission and a powerful 2W audio performance with enhanced fidelity (EN-FI) technology to ensure voice communication is clear, even in high noise environments. This is coupled with a unique water porting technology to expel liquid. The SC20 can also interact with wired or wireless body-worn accessories such as printers, barcode readers and RFID scanners. The product is enhanced with a QVGA sunlight-visible display, a smart menu feature, a customisable top-level screen, and a notification bar to allow customisable and rapid access to features and hundreds of soft key functions. The SC20 has the provision for adding modules to provide additional high-speed bearers or other functionality. One such module is Wi-Fi with support up to 802.11n.
The Sepura hand portable range is supported by fleet management tool Radio Manager 2. Up to 32 radios can be simultaneously updated per programming client application, making fleet-wide updates possible from local centres. It can also diagnose problems.
All the major manufacturers are adding new capabilities to TETRA handsets such as higher IP ratings, improved audio, smartphone like user-interfaces, and software platforms with rich applications. The market is vibrant and potential purchasers have an ideal venue for seeing and handling the latest devices at CCW in Amsterdam. We are now witnessing the introduction of hybrid devices where TETRA is complemented with LTE capability. Airbus Defence and Space, Sepura and Leonardo-Finmeccanica are adopting a modular approach to supporting LTE as full public safety capability has yet to be standardised in LTE. But using commercial LTE as a complementary bearer for non-secure but rich data makes sense even today.
