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Comment C=B*log2(1+SNR): It's not just a good idea... (Score 3, Insightful) 60

It's the law!

And you're getting very close to the Shannon limit with turbo codes. LTE isn't much more spectral efficient as compared to HSPA+, but it has wider frequency bands and so can get more peak speed to customers.

So you can increase the amount of spectrum you have, with the current infrastructure, to get more capacity. That will buy you a few years of network traffic increase.

But eventually you have to figure out how to get less capacity demand and more SNR. There's really only one way to do that: change the infrastructure topology. And that has lots of problems.

It's kind of like we're near "Peak Bandwidth".

Comment Ask Drew Curtis (Score 1) 214

Of He recently had to defend against one of these patent trolls. His advice on a TED talk was (if I recall): fight the infringement, not the patent. His response with a lawyer was actually pretty cheap, and asked the plaintiff to circle the infringement and to disclose various things about the shell company. The other side doesn't want battle in court, either. Drew settled for nothing.

Comment C is great (Score 4, Insightful) 793

  • It is much more portable than assembly
  • The performance overhead compared to assembly is reasonable
  • Most people find it simpler to develop in than Forth
  • It's not the horrible monster that C++ is

This makes it very nice for all kinds of embedded environments.

Efficiency matters. Python is great, but you don't want to use it for embedded work.

Comment He's mostly right (Score 5, Insightful) 406

All those scalar processors look the same. You can trade energy efficiency for performance and end up with a lower power processor that's a lot slower. When you push the performance, the architecture doesn't matter as much, because most of the energy is spent figuring out what to run and when to run it.

Compounding this fact, ARM isn't that great of an architecture. It's got variable length instructions, not enough registers, microcoded instructions, and a horrible, horrible virtual memory architecture.

The big thing that ARM has is the licensing model. ARM will give you just about everything you need for a decent applications SOC. Processor, bus, and now even things like GPU and memory controllers. Sprinkle in your own companies' special sauce, and you have a great product. All they ask is for a little bit of royalty money for every chip you sell. And since everyone is using pretty much the same ARM core, the tools and "ecosystem" is pretty good.

But there's not much of an advantage to the architecture... the advantage is all in the business model, where everyone can license it on the cheap and make a unique product out of it.

And nowadays, the CPU is becoming less important. It's everything around it -- graphics, video, audio, imaging, telecommunications -- is what makes the difference.

Comment This is why I like Google (Score 5, Insightful) 233

Google is at least trying to say "Hey, this whole patent troll environment sucks. You should really do something about this problem!"

Hopefully someone will listen to their complaint before they are forced to take matters into their own hands.

And I think everyone also sees the next step, which is retaliation. Google just bought all those Motorola patents, and having them shut down Nokia and Apple with all those 17-year-old cell phone patents would really be a step up in the Mutually-Assured-Destruction conflict, and everyone would suffer for it.

Taking this approach with the nukes in your back pocket seems much more civil than approach taken by the others.

Comment What do the numbers really look like? (Score 5, Interesting) 318

ITER is a hugely expensive project, and won't produce a commercially viable power generation system.

In a lot of areas where research is done on things which don't work yet -- rockets, bridges, transmission systems, etc -- there's a general idea of how things might be able to "scale up" to meet the goals.

Is tokamak fusion really in sight of being commercially viable source of energy? If we need unobtanium to make a commercially viable reactor, wouldn't it make sense to wait until the materials are viable before making even larger tokamaks? What do we learn from making these new, bigger, more expensive reactors?

Or are we trying to build ever-bigger spark gap transmitters as a way to make radio better? Maybe we should look at other schemes?

Or, alternatively, we know of a nice, large, gravity-fed fusion reactor fairly nearby, is the engineering simpler to harness energy from that on a large scale?

Comment Re:Can it be done effectivly without an FPU? (Score 2) 271

Sure. Most DSPs don't have floating point. Looks like the AVR has an 8x8 multiply, so that really helps. Most DSPs use 16x16 multiplies, accumulating with a 32 bit or larger accumulator. That's going to take several instructions on an 8 bit micro, but it's certainly feasible for things like audio with low data rates and small FFTs. On the other hand, if you're using an Arduino to do audio FFT for things like a spectrum analyzer, this technique won't help, since you're not interested in picking up a few signals, but all the frequency bands.

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