NTT Docomo has announced that they have developed a prototype of manhole type base station for the first time in Japan. They will be used in locations where there is no other infrastructure available in vicinity to host base stations. The antenna is installed at a depth of 10 cm under the ground, with a fiber connection to the radio equipment and the power supply are drawn from the ground by the underground buried piping. The service area is about 90 m radius.
Based on this, I am not sure if this is a complete small cell or just a remote radio head. I am inclined to think that this is a complete base station as its a standard LTE base station as per the specifications.
Manhole type base station specification (Sapporo verification station)
method
FDD-LTE
frequency
1.5 GHz band (BAND 21)
Bandwidth
15 MHz
MIMO compatible
2 × 2 MIMO
Downlink modulation scheme
256 QAM
Maximum Throughput
DL: 150 Mbps / UL: 37.5 Mbps
Size (buried part)
70 cm × 70 cm × 70 cm
Device size
About 29 cm × about 17 cm × about 7.5 cm
weight
Approximately 15 kg
Specification of manhole cover (Sapporo Verification Bureau)
size
Diameter 64.8 cm · thickness 5 cm
weight
Approximately 27 kg
Load bearing capacity
25 tons
The output power is not specified but base stations can easily fit within 15 kgs.
I have written about underground small cell here and here, which was about Swisscom, Ericsson & Kathrein trying it in Switzerland. I have also written about how the Japanese operator KDDI is trying to cover similar locations using lamp posts here. Its good to see Docomo trying something new.
As per the announcement, DoCoMo will work to improve the communication environment to areas where it was difficult to establish a base station, aiming for full-scale operation within the year 2018, and will continue to consider the application of future technologies to 5G in parallel.
From what I have heard, some antenna manufacturers are working on trying to convert the manhole cover in to an antenna. Its going to be a big challenge though.
Anyway, the new article says (translated by Google translate from Japanese):
In experiments, we used a street lamp that incorporates the base station function inside the pillar so that the antenna and the radio are not noticeable. We set up one in the parking lot adjacent to the municipal wreckage field in Yeomachiro and investigate tourist reactions on the landscape and the reach of the radio waves. The period is one year from October this year. Since the 5G base station has not yet been downsized, experiments predict the radio range using the current 4G base station.
So from what I understand (news sites here and here):
KDDI will be testing initially using 4G because 5G base stations are still quite big. It looks like a small cell but could be an RRH as well
This experiment will start in October and last a year
The Nepal disaster is another reminder that we need to be prepared in case of natural (or man-made) disasters and in times of emergencies.
ITU said that it has deployed emergency telecommunication equipment in Nepal following the 7.8 magnitude earthquake that hit the country on 25 April 2015. The emergency equipment includes 35 satellite mobile phones and 10 satellite Broadband Global Area Network terminals along with solar panels and laptops to support relief coordination efforts.
Satellite phones have been getting better with higher speeds. Thuraya Telecom has some interesting videos on Youtube, here is one that shows how to get good these phones have become:
Satellites can also be used to provide backhaul for small cells and can be installed relatively quickly.
Thaicom recently announced that they have sent equipment and engineers to help reconnect the region quickly. From a picture posted on their website, it looks like they are backhauling the small cells but I dont have any more details.
Drones (UAVs) and Baloons are another option for use in these scenarios but they need (expensive) receivers to be installed, which may be an issue.
One of the lessons learned after the Japanese twin disasters of earthquake and tsunami was the need to deploy more small cells.
According to Akiyoshi Ishiwata, a principal research analyst at Gartner in Tokyo covering Japan's mobile networks,'each of the operators are actively installing small cells and picocells in buildings, subways and indoor areas'. These miniature basestations improve indoor coverage, and improve a network's resilience by using more diverse power supplies and backhaul connections. Ishiwata said operators are considering using femtocells as the basis of a national machine-to-machine communications network that could also include earthquake sensors.
According to The Register, DoCoMo has tested blackout-proof hydrogen cell base station in Japan, ready for the next tsunami (see picture above).
Finally, I saw this tweet about Vodafone's emergency 'network in a back pack'
Vodafone prepares to launch emergency ‘network in a backpack’ in Nepal - 11kg mobile network which can be set up in just 10 minutes
Its not the first time Vodafone is helping out with a Small cell in a backpack. According to WSJ:
Vodafone Group said Monday its philanthropic division has created a mobile network in a backpack that can be deployed in 10 minutes, enabling aid workers to carry out their work in disaster zones.
The Instant Network Mini, which can be taken as hand luggage on commercial flights, can provide up to five concurrent calls within a radius of about 330 feet and enable text messages to be sent to thousands of people.
The 24-pound backpack is an innovation that follows on from the company’s original Instant Network—a portable network in a larger form that can be transported in four suitcases weighing 220 pounds. It offers a much wider operating radius of up to 3 miles.
Two original Instant Network kits were used in the Philippines during Typhoon Haiyan in November 2013, enabling 1.4 million text messages and 443,288 calls in 29 days, Vodafone says.
The backpack, developed by Vodafone’s Spanish business, as well as Chinese telecommunications giant Huawei Technologies and nongovernment organization Télécoms Sans Frontières, provides a secure 2G GSM network, with a GSM base transceiver station connecting to a host network over a satellite connection.
A 2G (short for second-generation) network can support voice calls and text messages but can’t easily handle Web surfing or video, unlike the 3G and 4G networks in wide consumer use.
In African countries, having a network allows people to use services like M-Pesa, for instant money transfers to friends and family. Vodafone has also donated £100,000 to support relief efforts following Nepal earthquake that killed more than 3,300 people.
While going through some KDDI presentations, came across how they planned and perform Offloading. In fact, even before the deployment of LTE, they were aware that the network capacity would not be enough for the savvy Japanese mobile phone users. They had to start planning for how to offload the users as soon as possible.
au Wi-Fi is their Wi-Fi offloading strategy where they make Wi-Fi hotspots available for the users. They even claim that with Wi-Fi on, the baattery life could be 1.5 times the normal 3G battery life.
UQ WiMAX is another KDDI company that allows users with compatible handsets to offload to WiMAX. KDDI have their own WiMAX branded services as well, see here.
Finally, with the LTE rollout they have different hierarchical cells available that the user could be moved to if one of the layers is congested.
