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Cognitive Radio (also known as "Opportunistic Spectrum Access") was first coined in an IEEE journal and is now considered the holy grail of communications research by many electrical/communications engineers.

To understand cognitive radio one must first be familiar with software radio. The operating parameters of a traditional radio (center frequency, modulation type, bandwidth, etc.) are defined in hardware and static in type. A software radio is a device which, in affect, brings the "software to the antenna" i.e. replaces the encoder/modulator/awgn/slicer with software. This allows much more flexible radio devices as they can use any frequency, with any modulation type, etc.

The next thing we must understand is that spectrum is scarce and increasingly expensive. The FCC's old spectrum licensing paradigm of fixed frequency assignment is outdated and can easily be improved. Here's an example: Verizon Wireless ownes (say) 1800 MHz nationwide and at all times but, if I could ensure little to no interference with Verizon's operations in the middle of the desert or at 4AM, shouldn't I be able to sub-license (or sub-lease) the spectrum?

This is where cognitive radio comes in: they scan the spectrum looking for "holes" (barely used frequencies), adjust their center frequency accordingly, find the best modulation type, etc. and transmit/receive at these frequencies. This will open up a lot of spectrum (the FCC noted spectrum utilization typically varies between 15% and 85%) and decrease the cost of spectrum access (or make the FCC a ton of money either way). The problem is that the engineering challenges are formidable (hidden terminal problem, collaborative sensing, etc.) and expensive (if we make a mistake, me might knock Verizon off the air) but eventually fixed licensing will be a thing of the past and we'll have devices that will operate at whatever frequency/modulation type/etc. they determine best and pay per usage (or some similar model).

For more info:

http://www.eecs.ucf.edu/tccn/(The Technical Committee on Cognitive Networks (TCCN) of the IEEE Communications Society)

http://www.ieeep1900.org/ (IEEE Cognitive Radio Information Center)

http://www.sdrforum.org/pages/aboutSdrTech/relatedTechnologies.asp (SDR Forum)

As someone else pointed out, the SDR Forum would call this device an SDR.

The SDR Forum defines tiers of software-ness. I've seen the terms used in the literature, so it's somewhat accepted.

• Sofware Defined Radio kits
• Elecraft kits
• PSK31
• APRS
• ARISS
• AMSAT

Its definately an FCC problem. The newest a/b/g chipset drivers are what's called "software defined radios". SDR is a major regulartory nightmare for the FCC because they can be reprogrammed by the user (more or less). Hence, the FCC wants to see infrastructure on the card to authenticate the code that runs there [kernel discussion]. Annoyingly.

The madwifi project is developing drivers for the Atheros a/b/g chipset. I've been using them and they appear to be reasonably good, for the moment. But, the distribute with a uuencoded binary blob that unpacks into a kernel module... I hear there are access points on the market that are basically Atheros a/b/g mini-PCI cards inside a plastic casing.

On the flip side, at least Intel sees the need to convince the FCC to open spectrums [quote]:

A third major challenge facing SDR technology is convincing the FCC to open the radio spectrum. In the past, the FCC has regulated specific radio bands for different types of communications. A radio device is then licensed for use in only a specific frequency range. Intel and other industry leaders would like to see devices licensed for multiple radio spectra, rather than for only one communications band. This would allow manufacturers to make a single device that could broadcast and/or receive at any appropriate frequency. The frequency used for a specific type of communication could then depend on the device or user identification, such as for National Guard, police, fire, Air-Sea Rescue, animal control, border patrol, road construction, clean-water works, and so on.

Future of user/subscriber go-everywhere & do-everything (GoDo for short) computing would include communications (GSM, WiFi 802.11x, Bluetooth, and IR/RF capabilities included). Still ... I would select Transmeta code-morphing processors as the technology edge for that future not Intel, Motorola, or TI ... though TI does now have a chip set that comes closer to the above stated goal for digital transmission systems. Transmeta code-morphing processors provide the ability to redefine operational spectrum requirements as you travel locally and globally with (I suspect, don't know?) less complex circuits/chip sets. The technology is known as Software Definable Radios (SDR). The future looks good to me ....

Related Links:

SDR.org - http://www.sdrforum.org/sdr_primer.html

TI DR Chip Set - http://www.eetimes.com/story/OEG20020109S0063

Transmeta - http://www.transmeta.com

Airship - http://wireless.iop.org/articles/feature/1/1/3/1

http://www.airship.com/prod/uses_telecoms_frames.h tm

OldHawk777

Reality is a self-induced hallucination.

Dbrower - you are absolutely rigght. All of this stuff about interference is pure BS. Software Defined Radio combined with Open Spectrum renders interference problems obsolete. Ironically, it was the military who invented software defined radio in the first place!

I would say this has more to do with either pure ignorance on the part of the DOD, or an excuse to squash this liberating technology.

Planet P Weblog - Personal Liberty with Technology.

Power:
Methane powered fuel cell, which provides for at least a months worth of continuous use.

The Screen:
Light emitting polymer screen is good here. Nice choice. The screen should also have some mechanism for eliminating finger grease automatically.

Form Factor:
A6, there should be no border, so that the screen takes up the entire front. Perhaps with fanned screens like the Psion Protoypes. (can't find a link)

Communications:
An array of Software Defined Radios, allows the device to keep in touch with the outside world. Depending on your current usage, they may be configured for Wireless Ethernet, BlueTooth, 3G+, TV, Radio etc. No need for multiple cards and slots. When a bug or security risk is found in any of the protocols, a simple software patch will fix the problem.

When data is huge, perhaps something like Infiniband over fibre optic would be useful.

Input:
Touch screen will be supported, along with a slide-out or otherwise concealed keyboard for when you actually want to enter some data. Voice recognition would also be nice, but only when your on your own.

CPU
Since were obviously way off into the future here, I would like a micro-distributed memory architecture, with approx 32 CPUs, each with at least 64 MB of memory. The CPU should probably be something like a 64bit ARM, running at whatever clockspeed is fashionable at the time. See this for similar stuff. The interconnects between CPU modules should use something like AMD's HyperTransport

OS
For linux fans, the CPU the architecture would support a micro-Beowulf style mode of operation.

For me, I'll roll my own Actor Model based system, running on a microkernel, like L4 but with better real-time response. Built in cryptography will keep ALL comms secure.