Wi-Fi Capacity Bottlenecks No More – Site Survey 5.5 Released!

We have released Ekahau Site Survey version 5.5. While it has a lot of new stuff, the major new thing is optimizing the capacity of an existing Wi-Fi network – and planning a wireless network based on the capacity requirements.

Believe me, it wasn’t easy implementing the capacity stuff. We wanted it to be accurate, which meant it would’ve easily also became hard to use. We spent countless hours in a meeting room, first trying to figure out how to solve the capacity problems, and then fine-tuning the user experience.

We really hope it turned out to be useful. Let us know how you feel about it!

PS. The English version is out first, and German & Japanese versions will be shipping within a few weeks.

With all those tablets and smartphones joining in, what about Wi-Fi capacity?

When designing a Wi-Fi network, you’re often asked for the minimum signal strength requirement.

When analyzing the wireless network, you’re shown a signal strength heatmap, plus perhaps data rate, access point overlap, all that stuff.

Is that all there is?

Today, we have all those smartphones, iPads, Galaxy Tabs, and Motorola Xooms utilizing the Wi-Fi network. Plus the increased number of laptops. And all this talk about replacing the wires with 802.11n.

May I suggest we also start considering capacity more carefully? I know a lot of Wi-Fi professionals have done this for years, but the Wi-Fi planning and analysis tools have lagged behind.

Until next week, that is. Stay tuned…

Regards,
Jussi Kiviniemi
Director, Product Marketing
Ekahau

 

Webinar This Thursday: Easier Wi-Fi Troubleshooting and Monitoring

I’m hosting a webinar this coming Thursday about how to make life a little easier for those of us who have to troubleshoot, analyze and monitor Wi-Fi networks.

It’s no secret I’ll be demonstrating Ekahau Mobile Survey, our brand-new Android phone/tablet based Wi-Fi tool there.

If you have time, register now and join in on Thursday at 10am pacific, 1pm eastern, early evening in Europe

I’ll also record the webinar (given we get no tech difficulties with the webinar system….)

—
Jussi

Ghost hunt powered by Ekahau! – Scared yet?

Fans of Syfy network’s show Destination Truth, hopefully you didn’t miss the live show this past St. Patrick’s day.

For those unfamiliar with the show, Destination Truth follows adventurer Joshua Gates and his crew in search for the truth behind the unexplained and legends around the world. This time, the crew and a few celebrity guest hosts were after the truth behind one of Ireland’s most long-living legends: the Banshee. The Banshee is a feminine spirit in Irish mythology, usually seen as an omen of death and a messenger from the Otherworld, i.e. the realm of the dead! The hunt for the Banshee took place in Duckett’s Grove Castle in Southern Ireland.

The live event featured several live online video feeds methods for fans to track the evidence and even included a map with the real-time location of each team member so viewers could keep track of their favorite team members. Most of the tracking was achieved using Ekahau RTLS Controller and T301BD tags, over a CISCO WLAN.

HOW ACCURATE IS IT? Part 3/3

In addition to the technological innovations described in the previous two articles, the location accuracy is also greatly affected by the environmental conditions and deployment methods. A voice-over-IP grade wireless network typically gives 1 to 3 meter accuracy with Ekahau and even better by tuning the network design for location systems. Additionally by careful and systematic deployment maximum and consistent accuracy can be achieved. Both, help with network design and deployment services, are provided by Ekahau’s professional services and certified partners.

By combining all these methods, the network and the engineering skills Ekahau is able to provide the best enterprise wide location accuracy in the industry with just using the existing, standard Wi-Fi network.

Even higher granularity for bed and sub-room level accuracy, and other hotspots, is achieved by using the Ekahau Location Beacon technology that uses low cost, battery powered infrared transmitters in locations where a high precision is required, and IR sensors embedded inside Ekahau Wi-Fi tags. The combination of RF (Wi-Fi) and IR technologies enable customers to deploy a reliable RTLS system with an enterprise wide visibility down to the bed-level accurate tracking. This also opens possibilities to variety of new emerging RTLS applications, such as hand hygiene monitoring, which are out of reach of less accurate RTLS technologies.

HOW ACCURATE IS IT? Part 2/3

The core innovation of Ekahau is the decision to use probabilistic modeling for location estimation. This innovation, which was patented in 2000 (US 7228136), was later extended with two other patents. The first one adds the time dimension to the model and the other describes how to build enterprise wide positioning models by combining site survey data (US 7349683 and US 7196662).

Filtering is an important mechanism to minimize jumps between floors, but is typically not enough to prevent floor hopping completely. By adding topology to the positioning model the algorithm is able to understand the ‘legal’ pathways that an object can use in the location area. Ekahau patented this “Rail Tracking” topology method in 2002 (US 7299059). This patent improves accuracy and is essential for preventing floor-hopping.

Wi-Fi Tags and other Wi-Fi devices have different radio characteristics that depend for instance on the radio silicon used, the RF circuitry and the mechanical design of the device. All these affect the radio transmission power and signal strength measurements of the device. To overcome the differences between different devices Ekahau uses a device normalization method that compensates the differences (US 11/029,642).

The latest addition to the series of algorithm innovations is to use particle filtering (http://en.wikipedia.org/wiki/Particle_filter) in the location algorithm. Particle filtering not only improves the location accuracy, but also enables scaling the system to very large, enterprise wide positioning models. The patent application for particle filtering in the context of location estimation was filed by Ekahau in 2005 (US 11/633,440).

These innovations provide a solid foundation for building real time location applications. Without these methods it is practically impossible to build a reliable and accurate Wi-Fi based RTLS system. In addition to the technology itself, however, the environment and the deployment process also impact the RTLS performance. With the next article of this series describes how these affect the location accuracy.

HOW ACCURATE IS IT? Part 1/3

The location accuracy of an RTLS system is a critical parameter as it determines greatly what kind of business benefits can be achieved with the system. An elementary accuracy of 10-15 meters can be achieved by almost any RTLS system, but how much value does it bring to the organization if the location is off by two rooms, or even a floor.

Some applications, such as wireless intrusion detection (WIDS), can live with less granularity, but several studies show that room level accuracy or better is required for most healthcare applications. Other industries have similar requirements on accuracy.

The simplest form of radio based location system estimates the location by the wireless access point the device is associated to.. This gives rough 10 to 50 m accuracy indoors, depending on the density of the network and the type of environment. This method, while being simple to implement, suffers greatly from its simplicity: If the tracked device is not very close to the access point, the accuracy will be weak. .

A bit more advanced location method is trilateration. With trilateration the signal strength is measured from multiple access points, minimum three, and the location estimate is calculated from these measurements. The accuracy is a bit better, but still weak (8 to 25 meters indoors, worse outdoors). The main issue is that trilateration assumes circular, “ideal” coverage patterns – but the Wi-Fi signals are heavily attenuated by walls and even the human body, making the coverage patterns all but circular. The method also suffers from multipath and noise.

By applying filtering to the above estimates the accuracy gets better and the random jumps of the location estimates become less frequent. Several commercial products and research projects have demonstrated that applying different filtering techniques, such as Kalman filtering (http://en.wikipedia.org/wiki/Kalman_filter), improve the accuracy. With filtering, the average accuracy can reach around 10 meters, but floor hopping still occurs frequently.
Ekahau’s location algorithms provide typically down to 3 meter average accuracy and 100% floor accuracy enterprise wide, over a VoIP grade Wi-Fi network. This location accuracy makes the Ekahau solution the leading Wi-Fi RTLS system on the market and with optional infrared technology this performance can be even further improved to bed level accuracy.

The next part of this article series looks into the innovations behind Ekahau’s location algorithm that enable industry’s best accuracy.

Ekahau RTLS-based Personal Emergency Call System can be a lifesaver!

In Fall 2010, the University Hospital of Innsbruck implemented the ProAct® personal emergency call system, which utilizes Ekahau real-time location tracking technology and the hospital’s existing Cisco wireless Network.  After a successful initial deployment, the solution has been expanded into the Emergency Admissions Department for Internal Medicine and is already proving its worth in improving patient care in emergency situations.

Staff members use purpose-built badge tags to quickly summon assistance in emergency situations. The system’s greatest advantage is that it utilizes Ekahau’s Wi-Fi-based RTLS technology, which enables hospital staff members to automatically specify the exact location from which each call for help is sent, which in turn speeds response time and improves patient care.

Patients in the Emergency Admissions Department for Internal Medicine have already benefited from the ProAct personal emergency call system and the Ekahau location tracking technology. In one case, a patient collapsed on his way to the bathroom. The nearest caregiver triggered an emergency call, and within a very short time several colleagues arrived to assist at the scene.

Romana Rössler, the nurse in charge of the station, said that the stricken patient was attended much more quickly than possible before. “In the past we had to briefly leave a patient and rush to a telephone, dial the number, and explain how to find our location. Precious time could sometimes be wasted in emergency situations,” she said. “Now I can instantaneously trigger an emergency call and then continue to devote my undivided attention to the patient. This system is a tremendous improvement. It benefits us on the staff; but also and above all, it can be a lifesaver for our patients.”