Dealing with Interference, Part 2 of 2
In our last post we started by comparing you and a friend chatting in a café while a very loud talking lady was interfering with your conversation.

How embarrassing would it be to tell your friend something three times and have them never even acknowledge that they heard you…ever. In the wireless world, that’s called message acknowledgement.
Without capacity, message acknowledgement isn’t possible for some LPWA providers because it’s just too costly to support in terms of network capacity. This leaves users of those technologies susceptible to failed messages. Not so with RPMA, we have message acknowledgement as well as intelligent retransmission schemes for failed packets so that the entire message doesn’t need to be resent. RPMA keeps the conversation normal and efficient, without wasted repeats, or missed sentences.
But wait, there’s more! Now imagine you and your friend can magically understand each other even with Loud Voice lady while both of you are whispering. RPMA can do that. We can detect signals that are weaker than interfering signals that share the exact same channel. Move a channel or two over from ours and the interfering signals can be way more powerful than ours and we can still pick it out nice and clean. It’s like a wireless superpower. Because of the nature of direct-sequence spread spectrum, and our industry leading receiver sensitivity (-142 dBm) we can find signals hidden deep in the noise.
Unfortunately, our narrowband brothers don’t have the same luxuries with interference. Their messages are easily destroyed by even the shortest bursts of broadband transmissions on the same frequency. RPMA is extremely robust to interference by virtue of our MAC’s ability to handle a 50% packet error rate. That means half the packets can be lost and the message still gets through. An RPMA message is like the Zombie that no matter how shot up it gets, it just keeps on moving. Except RPMA is nicer, and doesn’t want to eat brains.
You know that friend who is always cool with last minute changes in evening plans? That’s RPMA. RPMA transmissions adapt to match the available channel quality.
Our modules have transmit power control and our MAC continually adjusts the spreading factor to use the most robust waveform possible. Finally, we have 40 channels to work with in the US because of our available 80 MHz of bandwidth so we have a lot of breathing room. RPMA’s sophisticated MAC, wealth of capacity, and intelligent use of the spectrum makes it incredibly robust to interference. This robustness has been confirmed for years in actual commercial deployments. For years RPMA has supported extremely demanding industries who need reliable communication with their devices.
Put RPMA’s robust connectivity to work for you, contact us at info@ingenu.com or read more about how we deal with interference by downloading our white paper, How RPMA Handles Interference.


You know that friend who is always cool with last minute changes in evening plans? That’s RPMA. RPMA transmissions adapt to match the available channel quality.

As with many things, government regulations are the largest hurdle for most frequency bands, including the 900 MHz family of bands. However, the 2.4 GHz band has very favorable government regulations in both the US and Europe. For example, in the US, narrowband transmissions are restricted to 400ms (or 0.4 seconds), but this doesn’t affect RPMA as it utilizes direct-sequence spread spectrum (DSSS) modulation. +1 RPMA!

Fierce Wireless – September 29, 2015 – I’ve been thinking a lot about Mobile World Congress 2016 lately. In part, I’m just mentally preparing for a ski trip in Gstaad the week prior, the first time I’ve been skiing in forever (note: If you see me hobbling around La Fira in a cast, don’t ask). But there are also a handful of other reasons. CTIA’s Super Mobility Week just finished up earlier this month; while not approaching the stature of Mobile World Congress (MWC), it’s still one of the largest mobile-focused trade shows, providing insights into what we might see in Barcelona. Just prior to Super Mobility Week, we completed our first Mobile World Congress planning session with a customer. And since that was a cue to book my flight home from MWC, I soon realized that all the window seats are taken on any flight I’m likely to take. First world problems — I know.
For many years it has been more than acceptable to live within the limitations of consumer-grade battery life that offers comparable longevity to last night’s dinner. We are trained to fit the routine of plugging a cell phone into the wall on a daily basis. Likewise, we’ve been trained to think that as we develop M2M and IoT solutions that we must live within the same boundaries that restrict us as humans (i.e. cell phones, tablets, laptops). Those boundaries include depth and range of coverage, cost, and, of course, power consumption. The truth is that the wireless technologies that enrich our lives on one hand as humans are being used on the other hand as a retrofit to support a immense convoy of several billion machines that require an entirely different set of priorities and characteristics. Here are just a few considerations:
Industrial Equipment News – September 28, 2015 – Hey! Will All this IoT Stuff Mess Up Our LTE? Probably not, actually.
IoT Journal – Sep 28, 2015 –