Autonomous Relaying Drones

Came across this post from Prof. David Gesbert about the project ERC PERFUME are involved in. The post says:

Autonomous Flying Cellular Relay Robots

The team of ERC Advanced PERFUME project (www.ercperfume.org) at EURECOM under Prof. David Gesbert recently pioneered autonomous flying base station relays. The aerial robots  use machine learning to self-optimize their position based on suitable radio measurements and provide end-to-end enhanced connectivity to mobile users carrying off-the-shelf commercial terminals.  The communication layer builds on the OpenAirInterface developped at EURECOM's Communications Systems Department.

A first video was just unveiled here:


I have written about drones multiple times in the past (see here, here & here for example). Last week I looked at the relays (or Relay Nodes, RNs) as defined by 3GPP. We could safely assume that this autonomous relaying drone is Layer 3 Type 1a/1b RN.

I have heard multiple operators talking about this kind of approach where a person or group of people can get preferential services via drones in festivals and events. Of course it would make sense that these people are on some VIP package or emergency services workers.

Its an interesting concept but there will be many open questions. It would have to be tried for a long time to identify and iron out all the issues.

Do you agree / disagree?

"Vehicular CrowdCell" or "Vehicular Small Cell" and the 5G plan

In the recent Mobile World Congress, Vodafone and BMW introduced the Vehicular CrowdCell concept, a small cell providing coverage in the car when people are in it and outside when the car is parked. The presentation is embedded later on in the post.

The following is from the BMW press release:

...the BMW Group is unveiling the research project “Vehicular CrowdCell”. This project extends the concept of the “Vehicular Small Cell” presented last year in Barcelona. While the “Vehicular Small Cell” is a mobile femtocell that optimises the mobile radio reception inside vehicles, it is now also capable to enhance the capacity and coverage of mobile radio networks. The BMW Group is teaming up with peiker and Nash Technologies to present a prototype of the “Vehicular CrowdCell” integrated into a BMW research vehicle.

The rapid growth of mobile data traffic, e.g. due to the increasing use of multi-media services such as music or video streaming with mobile devices, requires even more powerful mobile radio networks in the future. One strategy to increase the capacity and coverage of future networks is the integration of a large number of small cells and relays in addition to the existing base stations.

In 2015 the BMW Group, together with its partners peiker and Nash Technologies, presented the world’s first mobile femtocell in a vehicle. The “Vehicular Small Cell” optimises the reception available to mobile devices inside vehicles via the vehicle’s aerial. Now the concept has been extended to create the “Vehicular CrowdCell”. Based on data traffic and coverage demands, the mobile femtocells are dynamically activated to locally enhance mobile radio networks.

The benefits of Vehicular CrowdCells in practice.
One possible application of “Vehicular CrowdCells” are car-sharing fleets – in particular with electric vehicles. Here, a large number of vehicles spread over cities and regions could serve as local radio relays when parked. If one or more users are located close to a mobile femtocell, it is activated on demand in order to increase the bandwidth or provide additional network coverage. In such a way, the performance of the existing network can be dynamically optimized. Benefits for mobile phone users in hotspots include a higher data rate and the absence of reception white spots – especially in areas where the signal coverage is low.

“The “Vehicular Small Cell” will optimise in-vehicle connectivity of mobile devices for our customers,” explains Dr. Peter Fertl, project manager at the BMW Group. “At the same time, the integration into a network of “Vehicular CrowdCells” will enable the ubiquitous and seamless availability of high-quality mobile radio connections outside the vehicle as well.”

Nash innovations have more details about the earlier version of this, The "Vehicular Small Cell" here and here.

Before we go any further, check out the Vodafone presentation embedded below:

I wrote a blog on this topic back in May 2014 here. In that article I mentioned that for a small cell in the car, the biggest challenge is backhaul. One approach is to use one particular frequency for backhauling to the small cell and then the small cells output another frequency. This approach was mentioned in another blog post here. In this approach, TD-LTE was used for backhaul and it created an FDD LTE small cell inside the train.

Why do I think this kind of approach work with 5G. In my other post about 5G spectrum, I mentioned that 5G will need multiple frequencies. Low frequencies for coverage, high frequencies for capacity and very high frequencies for very high speed throughput's. Because the very high frequencies, do not travel very far as compared to the low frequencies (with the same power), beamforming would be used. These very high frequency beams can be directed towards the Vehicular small cells, which in turn would create a much larger cell at a lower frequency.

This approach would typically only be used in urban environments as in rural areas there is plenty of unused spectrum (until more uses are found - quite possible with the IoT device explosion). The small cells would also need advanced sensing and SON capability to work in harmony with the macro network.

If you have an opinion, feel free to add it in the comments section.

Small Cells Network Sharing

Network sharing makes sense for the operators in this day and age when ARPU keeps going down and users expect more from their networks. The picture above shows the different components that can be shared to increase the cost savings.

Small cells sharing has been on agenda for a long time and it is starting to be deployed in the networks. I an interview with the new Small Cell Forum chariman, Alan Law, ThinkSmallCell covered this as a question:

What's your view on multi-operator Small Cell solutions?

Historically, there were a number of factors holding back adoption of multi-operator Small Cells, ranging from commercial aspects to technical aspects such as managing how the available capacity is shared between operators.

However, two 3GPP standards (MORAN and MOCN) have been defined which allow the same Small Cells to be shared between networks.

A few vendors and operators have implemented these features today demonstrating that there is no reason why Small Cells must be tied to a single operator

In another article featuring Radisys:

Can't Small Cells support multi-operator without DAS?

There are two existing 3GPP standards which do make this technically feasible. Both are already in commercial use today.
MOCN (Multiple Operator Core Network) is a network sharing concept that is fairly straightforward to implement, similar to network roaming. MORAN (Multiple Operator Radio Access Network) is more involved, providing a deeper integration and requiring more software within the small cells.

Some of our key customers are already using MOCN, but I see MORAN being the long term future – sharing the RAN as an end-to-end resource rather than just connecting through the core network. I can see a major challenge as we move outdoors to the streets where practical deployment constraints won't allow multiple small cells to be strung from the same lamp-posts.

I covered this RAN sharing in the 3G4G blog earlier here.

While the above picture is for the UMTS network, the LTE network sharing would be similar. Embedded below is a research paper that discusses the various approaches and to small cells network sharing and also features some case studies.

Shared Smallcell Networks from Zahid Ghadialy

Here are some additional links on this topic that would make an interesting reading:

• 3GPP Network Sharing Enhancements for LTE - Unwired Insight
• Active RAN sharing business models can bring benefits to towercos as well as operators - Analysis Mason
• LTE Network Sharing - Alcatel Lucent
• BIPT guidelines for infrastructure sharing
• Active RAN Sharing - NEC
• Case Study: RAN Sharing in Poland

Tight, Tighter and Very Tight Integration between LTE and WiFi Networks

For those who are unfamiliar about the trusted and non-trusted access, I strongly recommend reading our whitepaper on Cellular and WiFi Integration here.

The standard and the most popular Integration approach between LTE and Wi-Fi is via the Trusted architecture as shown above.

There is a proposal for RAN level Integration which would result in Even Tighter Integration of WiFi

Now some researchers are proposing a Very Tight coupling between LTE and Wi-Fi which would mean that regardless of the access, the UE can be sent data from the same data stream over WiFi and LTE. Though this is radical, these approaches are already being thought about for '5G'. Whether it will happen in a future release of 4G or 4.5G remains to be seen. Here is the complete paper embedded below:

Very Tight Coupling between LTE and Wi-Fi for Advanced Offloading Procedures from Zahid Ghadialy

Small Cells Research Bible

Here is a detailed research on Small Cells from Mehdi Bennis and Walid Saad presented in IEEE Dyspan 2014, this month. Feel free to add any comments for questions you may have.

Recent Advances in Wireless Small Cell Networks from Zahid Ghadialy