This is the second part in a three part series about cellular technologies in the rugged tech industry. Check out part one here:
Cellular Technologies in the Rugged Tech Industry Part 1 of 3
4G & 5G Networks
The G stands for Generation. 4G is the 4th generation cellular network while 5G is the 5th. 4G has been extended by the “LTE” which stands for long-term evolution. There has been a big push in the industry to get everything into 5G. This push is really just consumerism for the sake of consumerism. The end use device like a Panasonic TOUGHBOOK FZ-40 needs to be 5G compatible but the carrier also needs to have 5G towers built in order to actually send and receive the 5G signal from the computer. 4G LTE can reach speeds of 300 Mbps while 5G can reach speeds of 20 Gbps. Clearly 5G is capable of extremely faster speeds. That doesn’t mean it’s better, or at least not yet. Currently as of the publication of this blog, the average speed of a 5G network in the US is 100-200Mbps. This is firmly within the 4G LTE speeds. The carriers have not invested the money into the 5G towers to get the kind of network that is required for useful and fast operation. Many of the carriers started to have a little “5G” symbol on the phone to give the appearance of this network but it’s really just a push to get people to buy new equipment and activate more expensive plans without any real benefit to the customer. When it comes to 5G there are two main frequencies used. There’s mmWave (FR2) and Sub-6 (FR1). FR stands for frequency range. mmWave is what the carriers typically advertise. This frequency range allows for the faster speeds up to 20 Gbps however the average speed is more like 2 Gbps. The biggest draw back of mmWave is that the signal gets easily disrupted by physical options. That means buildings, trees, cars, etc all cause the signal to dramatically reduce to a point of potentially being unusable. This requires an extensive network of towers that is frankly not economically viable for any carrier to setup. This would be more likely utilized in a private network setting. Sub-6 FR1 has a lot of overlap in the frequency bands being used with 4G LTE. This allows the carrier to use the previously used and considered 4G LTE signal but rebrand it as 5G. There are new bands that allow for up to 700 Mbps. The range of the Sub-6 FR1 is significantly better and the signal penetrates through solid objects like buildings, cas, trees, etc. When you look at what the speeds are and what the current state of market demand is the requirement for 5G is not there. 20 Mbps is a perfectly adequate speed to browse the internet, use email, and even stream media. If you wanted to play graphically demanding video games on the internet you’d want to get a low latency speed of closer to 60 Mbps at least. 4G LTE and 5G sub-6 speeds are going to more than cover the US internet speed demands for the next 5-10 years while the network continues to be worked out. The key takeaway is don’t feel any fear of falling behind by not getting 5G tech while 4G LTE works perfectly fine and will for years to come.
Cellular Signal
A cellular carrier company like Verizon sets up thousands of towers across the country to create the cellular network that we know and use today. Cellular towers range from 50 to 400 feet. Taller towers are typically found in rural areas because they can shoot the signal over a longer distance but each tower has a limit on how many devices can connect so you don’t find too many tall towers in urban areas. The challenge to signal is even if you can put up a big tower that can shoot signal for miles around it doesn’t mean that devices will be able to connect. Cellular signal works in “duplex” which means the tower’s distance is important but the device itself needs to be able to transmit back. Height of the tower and the power pushing the signal make a huge impact on how far a signal will go. Say you have a tower setup that can push signal for 10 miles. You may think that anyone in a 10 miles radius could then connect to that tower. Unfortunately do to the duplex nature of the signal that is not the case. The cellular modem on the laptop is not as high as the tower, as big as the tower, or using as much power to transmit the signal. This means the TOUGHBOOK or Getac Laptop with the cellular modem may only be able to shoot a signal 3 miles away. This means that while the tower itself is pushing signal 10 miles out, the devices connecting to it have to be able to send signal back in order to get service. The way to improve this is to either have more towers or to increase the signal of the device you are using. Some cellular devices like cell phones really can’t change the power of their signal. Some Rugged Laptops like the TOUGHBOOK FZ-G2 or Getac F110 can have pass through setup through the tablet into a vehicle docking station. This allows for a far bigger and stronger “donor” antenna to be setup on top of a vehicle or mounted to a building. This larger antenna is able to send the signal over a longer distance. The FCC limits how much power can be used by a personal cellular device like a laptop or cell phone. In an effort to allow critical life saving first responders to have the best possible signal the FCC allowed the FirstNet carrier group to develop and implement High Power User Equipment or HPUE. This is also branded as MegaRange. This allows the device to use more than the originally FCC limited amount of power allowing the device to get a significantly stronger signal.
Antennas
The size of an antenna is one of the most important attributes to its quality. Many talented engineers have found ways to make more compact antennas while maintaining quality but the bigger the antenna usually the better it will perform. Another aspect of an antenna are the elements of it. The element of an antenna is what kind of signal is being captured and the cable that connects the antenna to the device. For example Ericsson Enterprise - formerly Cradlepoint - creates a cellular modem designed to be used inside the vehicle. This model can have quite a few different signals brought in through the antenna. There can be multiple WWAN (cellular), GPS, AUX, and WiFi. If an antenna had 11 elements it would be considered an 11 in 1 antenna. These connections are then terminated to connect to a device. It is important to pay attention to how these devices connect. The most common termination in the industry is the SMA connection but many of the rugged laptop industry like TOUGHBOOK and Getac have used TNC connections.
Check out the upcoming Rugged or Die blog for the 3rd and final part of our 3 part series about cellular connectivity and how it applies to the rugged computing world!
