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Suppose for a moment that we had arrived at this digital epoch, but had only just discovered wireless. Would we start by designing and building the wireless systems we now take for granted? I think not! The reality is; today’s wireless thinking is largely set by developments stretching back well over 100 years, and constrained by the limited physical models and mathematical ability of that time. Concepts such as LF, HF, VHF, UHF, SHF - Long, Medium and Short Waves - and dedicated channels are a result. So deep is all this that some actually think the ‘frequency domain’ is real as opposed to an abstract engineering convenience. Every aspect of wireless communication we enjoy today stems from old analogue thinking and there is very little in this digital era that we could truly consider to be radically new. In truth, our digital radios are really analogue at their core, and so is the very way we think. So a manifest for change might include: No more bands or channels No government regulation or control The EM spectrum used as a continuum Communication @ minimal energy Operating below the thermal floor Orthogonality through coding Massive spread factors Micro networking
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A Wireless Future M a k i n g W a v e s
Peter Cochrane
cochrane.org.ukca-global.org
COCHRANE a s s o c i a t e s
T h e r e i s n o d i g i t a l wireless…only ana logue systems we have bent to our digital bidding….
Suppose for the sake of argument we had derived all our technologies without discovering or the need for wireless technology… !
…but this morning we stumbled across EM waves and the possibility… !
…would we go along the same development path of our forbears and go for bands and channels ???
Impossible
I know but
please,just
humour
me
Would we be thinking: !- 2.5/3.0kHz for voice telephony ? - 9/10kHz or AM Broadcast Radio ? - 200/700kHz for FM Stereo Music ? - 6/8MHz for NTSC/SECAM/PAL TV ? - 20/36MHz for satellite transponders ? !!!!!- LW, MW, SW, VHF, UHF, SHF +++ ? - Channels per each user/application ? - Bands for groups of similar users ? !- OFCOM, FCC, Government ?
Would we be thinking: !- 2.5/3.0kHz for voice telephony ? - 9/10kHz or AM Broadcast Radio ? - 200/700kHz for FM Stereo Music ? - 6/8MHz for NTSC/SECAM/PAL TV ? - 20/36MHz for satellite transponders ? !!!!!- LW, MW, SW, VHF, UHF, SHF +++ ? - Channels per each user/application ? - Bands for groups of similar users ? !- OFCOM, FCC, Government ?
I think not !
Would we delude ourselves with the distorted view presented by band plans like this ?
Or would we give all this deep thought and come up with a succinct set of objectives :
“The maximal exploitation of the EM Spectrum to the advantage of Man and Machine for the purposes of communication, sensing, manipulation, and processing”!!!!!!!“And we should exploit the ‘spectrum space’ to best advantage including performance, sustainability and longevity”
Howdid
wege
t her
e?
With coils, capacitors, resistors, tubes/valves - analogue was the best you could do - digital was all but impossible …you could only exploit the signal selectivity by resonance, high and low pass filters, use amplifiers, oscillators and modulators…
Because of this our wireless history is ‘fork lift’, with radio receivers & transmitters that were
big, very big, consuming vast amounts of energy and raw materials - weighing
tons and eating kW of power to serve/reach vast regions
of countries/ the planet
And a trend that has not improved a
lot at the head end over the decades
!however
distances are now shorter
These created the opportunity for fundamental change….
!11
Without the transistor, integrated circuit, pcb, surface mount components, and the possibility of digital
formats, there was no place to go other than making it smaller, cheaper and prettier,
but that is all we have done since and it really is time to move on
& think anew
Without the transistor, integrated circuit, pcb, surface mount components, and the possibility of digital
formats, there was no place to go other than making it smaller, cheaper and prettier,
but that is all we have done since and it really is time to move
on and think anew
It really is time to move our thinking on beyond this past era
From this…
To this…everyone and every thing on line ~ 9Bn
people + >50Bn things…we need
bandwidth and connectivity
ks
Bns
Sensors RFID
Mobiles 3/4/5G
Tns
Ms
WiFi/Max100ks
ks
Bns
Sensors RFID
Number Tx of devicesMW
mW
Distance & Power
Mobiles 3/4/5G
Tns
Ms
WiFi/Max100ks
ks
Bns
Sensors RFID
Number Tx of devicesMW
mW
Distance & Power
Mobiles 3/4/5G
Tns
Ms
WiFi/Max100ks
100% The need for regulation and control ~ 0%
Personal Space
Bluetooth UWB RFID
LAN MAN WANPAN
City Community
WMAN WiMAX Beam Forming
Cellular/Satellites International
HSDPA WCDMA UMTS
WLAN 802.11X WiFi
Campus, Office, Airport, Home
The dream….…seamless access!
3m 30m 3km Ubiquitous
Personal Space
Bluetooth UWB RFID
LAN MAN WANPAN
City Community
WMAN WiMAX Beam Forming
Cellular/Satellites International
HSDPA WCDMA UMTS
WLAN 802.11X WiFi
Campus, Office, Airport, Home
The dream….…seamless access!
3m 30m 3km Ubiquitous
C Cameras - VOIP - Sensors - Positioning +++
Thin bandwidth over 1 - 10km
You can’t beat the laws of
physics
Big bandwidth over 1 - 10m
The spectrum myth…
…it is in short supply!
The spectrum myth…
…it is in short supply!
Actuall
y it is
mostl
y unu
sed!
The spectrum myth…
…it is in short supply!
Actuall
y it is
mostl
y unu
sed!
City of Chicago study <17% of commercial spectrum used
Not a lot of occupancy here and this is a wifi band in London…and the rest of the planet is the same !
The distorted perception of a logarithmic scale
All human created wireless energy is currently concentrated here
But there is 30x more unused space here
We have devices & processing power to do & access more than ever before…>30GHz…
FM
We have devices & processing power to do & access more than ever before…>30GHz…
FM
TV
We have devices & processing power to do & access more than ever before…>30GHz…
FM
TV
Mobile
We have devices & processing power to do & access more than ever before…>30GHz…
FM
TV Optical
Mobile
We have devices & processing power to do & access more than ever before…>30GHz…
FM
TV Optical
Mobile
WiFi
We have devices & processing power to do & access more than ever before…>30GHz…
FM
TV Optical
Mobile
WiFi
We have devices & processing power to do & access more than ever before…>30GHz…
Opp
ortu
nity
We now have the technology to deliver an infinity of wireless bandwidth to almost any location...all the old limiters have gone!
Sheer computing power (will just about) solve all the old propagation problems…
• Signal processing allows (extreme) spread spectrum modes • Auto power, channel and mode control made it all black boxes • Spatial processing mitigates self/others interference • Smarts negate need for regulation, band structures, frequency allocations
Adaptive Antenna Base Station
S/N dB
BW Hz
Duration
T seconds
Back to Basics: In format ion transmitted over a channel expressed as a volumetric function of S/N, BW and Time - aka Claude Shannon 1945/46
C = B.T log2(1 + k.S/N)
C ~ B.T.K.S/NdB
vv
S/N dB
BW Hz
Duration
T seconds
B a c k t o B a s i c s : T h e s a m e information transmitted over a channel in three different modes using S/N, BW and T as variable factors - aka Claude Shannon 1945/46
Today and The Past: The outmoded and largely dying past of analogue transmission in distinct and defended bands
Today and The Past: The outmoded and largely dying past of analogue transmission in distinct and defended bands
Today’s digital systems look very similar with bands
and channels - QUAM, QPSK et al are wider, suffer the loss of
guard bands, plus interference and intermodulation +++
300Hz 3500Hz
Uncoded Baseband Speech
Parsed and Ordered Baseband
Parsed and Randomised Baseband
A Bit Of History: WWII Speech coding using channel frequency parsing, random sideband inversion and re-arrangement
The Cold War: Frequency hopping spread spectrum - ‘catch me if you can’
S
f Hz
time
Dwell Time
The Even Colder War: Frequency hopping variable dwell and hop time SSBSC spread spectrum
S
f Hz
time
Hop Time
Subversive Communication: Frequency spreading analogue SS
f
f
f
t
t
t
tX
Modulator/ Multiplier
Analogue Input
Analogue Output
Spreading Sequence 2.5kHz of speech spread over
2.5, 25 or 250MHz hidden by the thermal noise - undetected
and unheard
All Digital Future: How a digital future without bands employing Sequence Spreading might look
Get in The Noise: An interfering DSBSC signal creating a minimal interference threat and vice versa
DSBSC Signal well above the noise
Thermal & Cosmic Background Noise
Spread Spectrum Signal well under the noise
Frequency and amplitude axis not to scale
EG: Speech/Music BW = 12kHz BW = 2GHz
Big Challenges: !Antennas spanning
very wide bands are
non-trivial…and any
form of beam steering
forms an even bigger
challenge
Big Challenges: !Devices providing the
necessary performance
might be demanding
but there is a lot on the
market if we think and
innovate…
Big Challenges: !Signalling & Sync at
speed will demand
original thinking and
development as the
p ro toco l s do no t
exist…
Supporters: !Very encouraging and
keen to see the UK
t a k e a l e a d i n g
position in this line of
work…organising a
series of industry
days..and wish to see
universities in the play
Supporters: !A very small % of the
HAM radio fraternity
are interested and
looking to this to
revital ise a dying
hobby
The Next End Game ?
More Data Carried:
Telegraph >> Messenger
Telephone >> Telegraph
Mobile >> Telephone
WiFi >> Mobile
Internet >> All Above
Clouds of Things >> Internet
The Internet will not scale functionally or economically, but Clouds will - and ‘thing-to-thing’ communication will eclipse all before
Thank You
ca-global.orgcochrane.org.uk
COCHRANE a s s o c i a t e s
