doc.: ieee 802.15-05-0052-01-004a submission january 2005 dani raphaeli, gideon kaplan (sandlinks)...
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January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 1
doc.: IEEE 802.15-05-0052-01-004a
Submission
Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)
Submission Title: [TG4a-SandLinks-CFP-Presentation]Date Submitted: [4 Jan, 2005]Source: [Dani Raphaeli, Gidi Kaplan] Company: [SandLinks]Address: [Hanehoshet 6, Tel Aviv, Israel]E-Mail: [[email protected]]
Re: [802.15.4a Call for proposal]
Abstract: [A proposal for the P802.15.4a alt-PHY standard]
Purpose: [Response to WPAN-802.15.4a Call for Proposals]
Notice: This document has been prepared to assist the IEEE P802.15. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein.Release: The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P802.15.
January 2005 doc.: IEEE 802.15-05-0052-01-004a
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 2Submission
Low-Rate UWB Alternate Physical Layer
Proposal Submissionfor TG 802.15.4a
Jan ‘05 Meeting
Dr. Dani Raphaeli & Dr. Gideon KaplanSandLinks
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 3
doc.: IEEE 802.15-05-0052-01-004a
Submission
Outline• General Overview• Signal and Packet design• Communication Performance
– Sensitivity, Acquisition– Interference & Coexistence– Aggregate Rate
• Ranging• MAC Protocol Considerations• Block Diagrams and Technical Feasibility• Cost/Complexity• Scalability• Power Consumption• Summary
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 4
doc.: IEEE 802.15-05-0052-01-004a
Submission
Technical Requirements of TG-4a
• Low complexity and cost• Low power consumption • Precision location (highly desired – relative rangingrelative ranging)• Extended range• Robustness (against MP, against interference)• Mobility • Low bit rate for each individual link• High Aggregated rate at a collector node• Random, ad-hoc, topology• Work under current 15.4 MAC
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 5
doc.: IEEE 802.15-05-0052-01-004a
Submission
General Overview of Proposal
• Symbol Interleaved Impulse Radio• 500Mhz bandwidth in UWB band
– Optional: 80Mhz in 2.4GHz, 200Mhz in 5.2 Ghz• May choose (program) one of several Center Frequencies • Use of Round Trip Delay for ranging• Low data rate per device allows to obtain PER and
Ranging within substantial distances, for various channel models
• High total (aggregate) rate • Suitable for very low-cost (small die size) implementation
in a standard process• Robust, Flexible and Scalable solution.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 6
doc.: IEEE 802.15-05-0052-01-004a
Submission
Symbol Interleaved Impulse Radio Basic principle: Use pulse trains with constant large separation
between them. Each pulse train represents one symbol. Pulse train (or sequence) is used instead of single pulse to decrease
peak to average, which serves to:• Simplify implementation
• Meet FCC peak power constraint in the UWB band
Pulse sequence polarity corresponding to the 11 bit barker sequence 10110111000
~100ns
~20s
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 7
doc.: IEEE 802.15-05-0052-01-004a
Submission
Symbol Interleaved Impulse Radio (cont.)
Many users can transmit concurrently without interference:
(each color represents a different packet from a different user).
~20s
Substantial aggregate rate can be achieved (see in the sequel); the transmission management mechanism of 15.4 is appropriate.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 8
doc.: IEEE 802.15-05-0052-01-004a
Submission
Benefits
There is no need for a difficult and slow synchronization process (incurred if several / long sequences are used)
Easy implementation
Passes FCC rules
Reduced sensitivity to Multipath (see figure below)
Near-Far Problem is minimized.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 9
doc.: IEEE 802.15-05-0052-01-004a
Submission
Signal (Pulse) Design• A look on an actual pulse train symbol (fc=4GHz)
• Zoom on a single pulse
• For average and peak powers- see Appendix A
8.5 9 9.5 10 10.5 11 11.5 12 12.5 13 13.5 14 14.5 150.2
0
ns
0 10 20 30 40 50 60 70 80 90 100 1100.2
0.1
0
0.1
0.2
ns
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 10
doc.: IEEE 802.15-05-0052-01-004a
Submission
Signal (Pulse) Design• A look on an actual pulse train symbol (fc=4GHz) in the
frequency domain, Pt=-15dbm
3 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 4 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 570
60
50
40
GHz
dbm
/MH
z
51
41fc 0.25 fc 0.25
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 11
doc.: IEEE 802.15-05-0052-01-004a
Submission
Packet Structure Design
• Preamble (un-modulated) part enables to synchronize on received signal and for receiver acquisition and training.
• Data part uses PPM (binary, possibly M-ary) to convey message [SPDU]. Message lengths – between 7 to 128 Octets (MAC limit). Nominal symbol rate is 50Ksym/sec.
• Response (un-modulated) part allows for synchronous Ack (see in the following) plus data response.
• Total packet length – typically 10 to 20 msec.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 12
doc.: IEEE 802.15-05-0052-01-004a
Submission
Packet Structure
PPM
Preamble DATA (MAC fields)Response Period (optional)
Unmodulated Unmodulated
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 13
doc.: IEEE 802.15-05-0052-01-004a
Submission
The Response Period
ACK Preamble
Response Period
ACK DATA
The ACK is transmitted during the response period of the original Packet.
DATA
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 14
doc.: IEEE 802.15-05-0052-01-004a
Submission
The Synchronous ACK
• The ACK is transmitted during the response period of the original
packet thereby allowing synchronization of the response to measure the channel round trip delay.
• The Response Period duration is minimally equal to the ACK preamble duration, and at maximum lasts for the entire ACK
• The response (the ACK) is transmitted at a fixed (known) delay relative to the RP pulses. The Node receiving the ACK can measure the RTD and calculate the distance accordingly.
• The symbols of the RP are used for synchronizing the response – This allows the use of low accuracy clocks, which serves to:
REDUCE THE COST MINIMIZE SYSTEM COMPLEXITY (MAC/higher layer not
involved in generating accurate time base)– Since the ACKs are transmitted at a fixed delay, ACK collisions
are avoided as long as the original packets were not colliding
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 15
doc.: IEEE 802.15-05-0052-01-004a
Submission
Topology & Types of Devices
The 802.15.4 defines two types of devices:• The low complexity RFD (Reduced Function Device) which
can be only a leaf on the network. • The full complexity FFD (Full Function Device).
• A typical topology composed of manymany RFDs as the sensors or tags and fewfew FFDs as coordinators and data concentrators.
• The topology may change in the network.
PANcoordinator
FFD
RFD
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 16
doc.: IEEE 802.15-05-0052-01-004a
Submission
Types of Devices (cont)
• We propose asymmetric PHY: FFD with higher functionality and higher
cost and RFD with lower functionality and cost.
• The ultra low cost RFD (Reduced Function Device) is notnot required to be able to receive multiple packets. It will be capable of:
– Responding to FFD requests.– Sending packets to a FFD– Requesting for a pending packet
• The FFD (Full Function Device) is expected to be able to receive simultaneous multiple packets concurrently. It will be capable of:
– Receiving many packets at the same time and responding each of them with ACK.
– Calculating the distance to each node it received ACK from– Responding to RFD data requests.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 17
doc.: IEEE 802.15-05-0052-01-004a
Submission
Communication Performance – PER vs. Eb/No
• The chosen modulation is PPM• Coding scheme is still TBD. We use simple (63,57) Hamming code (and
hard decision decoding) for the current presentation; however obviously other codes, still simple to implement, exist with a higher coding gain.
• For 32 octets, to get PER of 1%, the BER should be
BER <= 0.01/(32*8)=4e-5• In the next slide, the theoretical results show that Es/N0=11.5dB is
required
• In AWGN channel, for 50Ksym/sec, d=100m is achieved with ~6dB of margin.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 18
doc.: IEEE 802.15-05-0052-01-004a
Submission
Communication Performance – Theoretical BER vs. Eb/No
4 5 6 7 8 9 10 11 12 13 141 10
10
1 109
1 108
1 107
1 106
1 105
1 104
1 103
0.01
0.1
1
PPM (uncoded)PPM (coded)
Theoretical BER performance
Es/N0 (dB)
BE
R
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 19
doc.: IEEE 802.15-05-0052-01-004a
Submission
Link Budget (AWGN channel)
Nominal Proposed parametersPeak payload bit rate 50.00 Ksym/secAvg Tx power -14.30 dBmTx Ant Gain 0.00 dBiFc 4.00 GhzPath loss at 1meter 44.48 dBd 100.00 meterPath loss at d meter 84.48 dBRx Ant Gain 0.00 dBiTx Backoff 3.00 dBRx loss 0.00 dBRx rcv power -101.78 dBm
Avg noise power per bit -127.01 dBm (per Rb)Rx Noise figure 7.00Avg thermal noise power -120.01 dBm
Min Es/No 11.50 dBImpl loss 1.00 dB
Link Margin 5.73 dBProposed Sensitivity -107.51 dBm
Pathloss+Margin 90.21 dB
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 20
doc.: IEEE 802.15-05-0052-01-004a
Submission
Performance under Multipath
• From the link budget: Receiver Sensitivity is -107.5 dBm; or, total path loss <=90dB.
• Achievable distances for the 9 channel models defined by the TG4a channel modeling subgroup, are shown in the next slide.
• PER performance on these channels was checked by system simulation. The simulation includes: Acquisition Tracking Adaptation Demodulation Decoding Packet processing
• The PER results for several channel models (presented next) show good match with the theoretical predictions.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 21
doc.: IEEE 802.15-05-0052-01-004a
Submission
Distance vs. Channel Models[50Ksym/sec]
CM Type of Channel Distance [m]
1 Resident. LOS 394
2 Resid. hard NLOS (concrete walls*)
8.2
3 Office LOS 1610
4 Office NLOS 20.6
5 Outdoor LOS 421
6 Outdoor NLOS 75
7 Industrial LOS 421
8 Industrial NLOS 27
9 Farm 393.5
*The high atten. In 15-04-0290-02-004a taken from 802.15-02/444
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 22
doc.: IEEE 802.15-05-0052-01-004a
Submission
PER curves
•
Simulation on Channels Packet length=512 bits, Hamming code
0
0.01
0.02
0.03
0.04
0.05
11 12 13
Es/N0
PE
R
CM1
CM2
CM3
CM4
CM5
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 23
doc.: IEEE 802.15-05-0052-01-004a
Submission
Acquisition
• We assume the super-frame structure includes a Beacon transmission• In a steady-state, all devices synchronize to the Beacon transmissions
of the PAN coordinator• A quick re-acquisition (in a short length window), to re-align the
timing, is performed per each received Beacon. • The device then listens in the address message space to check if data is
waiting; otherwise (if the device does not need to transmit) – it goes back to sleep
• The quick acquisition is performed over the standard 4 octets preamble of the Beacon packet
• All normal transmission packets will also include a 4 octets preamble, used for fine timing acquisition + channel model learning.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 24
doc.: IEEE 802.15-05-0052-01-004a
Submission
Acquisition (cont.)
• In case a new RFD/FFD device joins an existing network, it has first to synchronize to the super-frame structure (namely to the Beacons transmissions)
• One possible mechanism is passive association
• Assuming that the power consumption dictates no more than about 1% duty cycle over long periods, this passive process will be relatively slow in time.
• If active association is used, faster synchronization can be achieved.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 25
doc.: IEEE 802.15-05-0052-01-004a
Submission
Interference & Coexistence
• Protection against WLAN and other out of band signals (in 2.4Ghz, 5.3Ghz) aided by a 3rd order Band-Pass filter in the receiver (or an equivalent LPF after down conversion)
• For narrow-band interference (in-band), – High processing gain inherent in the technique (500MHz/50KHz=40dB)– Adaptive or programmable interference rejection mechanism (with mild
requirements) may be employed
• A real life effect which should be considered, is the transmission of “wide band noise” (OOB) by other devices, which covers the same freq band as the UWB device
• • The result show that at most 1m separation insures meting the criteria of
PER<=1%, for UWB signal level 6dB above sensitivity level• For detailed analysis see spreadsheets in submitted material.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 26
doc.: IEEE 802.15-05-0052-01-004a
Submission
Interference & Coexistence (cont.)
• Under extreme interference cases, a change of the active band may be undertaken (under higher layer command).
• Coexistence with other devices (802 type, Vsats,..) is achieved with a small distance separation, due to the low average power density level of UWB transmission (detailed analysis in submitted material)
• Co-existence with other Piconets – possibly co-located – may be simply achieved by selection of different active frequency bands for the Piconets (up to 3).
• The band select filter provides more than 20dB attenuation, even for the adjacent bands of 4Ghz (centered at 3.5Ghz, 4.5Ghz).
• Further simulation results will be provided later on.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 27
doc.: IEEE 802.15-05-0052-01-004a
Submission
Band Plan
• The analysis (e.g. Link Budget) was made with a Fc=4Ghz (Fl=3.6Gh, Fh=4.4Ghz for -10dB points)
• The UWB freq range can be divided to multi-bands, coordinated with other uses defined by the ITU and IEEE bodies
• Typically a device may be programmable to one of 3 bands in the range 3-5GHz (and additional bands in 6-10GHz when higher speed processes will be cost effective)
• This enhances the robustness of the design and may serve to improve acceptance by regulation bodies worldwide
• Outside the USA, device will operate in 2.4GHz or 5.2GHz until UWB will be approved worldwide.
• Nevertheless, since the high aggregate rate (~10Mbps) enables virtually all multiple uses in the same area, the standard should allow for lower cost devices to be fabricated for one fixed band.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 28
doc.: IEEE 802.15-05-0052-01-004a
Submission
Aggregate Rate Considerations
• Recall the Interleaved pulsed transmission proposed • There are N=200 virtual time slots (of Ts= 100nsec), totaling 20usec,
between each transmitted symbols of a single packet
• The transmitting / answering devices can chose one of the N virtual time slots, to transmit their packet
• This choice is kept throughout the packet
• Due to the possible spatial layout of the answering devices, round trip delay differences can be larger than Ts.
• Thus the basic model is multi-channel (N) un-slotted Aloha
• The throughput vs. offered load of such a channel is known, and its peak is 1/2e (per slot).
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 29
doc.: IEEE 802.15-05-0052-01-004a
Submission
Aggregate Rate (cont.)
• The ALOHA model assumes that if more than one transmission uses the same slot, than there is a collision and none gets through
• Recall the Barker sequence (of length 11) Processing Gain, allowing for more than one reception in a time slot, if their sequences are in shift
• However some issues like Near-Far (power ratio) and also channel multipath come into play
• First analysis estimates that the effective PG is about 3; further simulations are needed to justify this estimate.
• Thus the scheme has 3N effective slots, so the maximum aggregate rate is
3*200*(1/2e)*1/50usec = 5.5Msym/sec.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 30
doc.: IEEE 802.15-05-0052-01-004a
Submission
Aloha Curve(s)
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0 0.5 1 1.5 2
Unslotted Aloha
CSMA-CA, a=0.3
Throughput
Load
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 31
doc.: IEEE 802.15-05-0052-01-004a
Submission
Aggregate Rate (cont.)
• For a ALOHA channel, insuring stability is of importance, by employing simple anti-congestion (“back-off”) mechanisms
• Usage of Guaranteed Time Slots (GTS) can further improve the capacity, as these will operate at close to 100% efficiency;However this mode is applicable especially to relatively long transmissions.
• Employing a collision avoidance (or CCA) mechanism, performance is improved in the (contention-based) Aloha slots as well as the stability
• With CCA employed, for a propagation delay of ~30nsec, and transmission of 100nsec, theoretical capacity grows up to to
Capacity = 9.6Mbs
• The transmitting / answering devices hear only a partial population of all devices, thus the actual performance improvement of CCA will be assessed via a simulation (per specific channel and node locations).
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 32
doc.: IEEE 802.15-05-0052-01-004a
Submission
Ranging
• Basic method proposed is Round Trip Delay measurement (by a FFD).
• Why should we choose RTD for 15.4a?– No need for fixed expensive infrastructure.– No need to generate a very accurate time base.– The only one that can be used in RelativeRelative systems. – Each node makes its own measurement autonomously.– Easy to handle Multipath (take the earliest component).– Straightforward to implement.– Can handle distance measurement with a single node in case x,y,z
coordinate is not necessary.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 33
doc.: IEEE 802.15-05-0052-01-004a
Submission
Ranging (cont.)• Ranging is performed at same distance coverage as is for communications• The ranging algorithm uses between 30 to 50 symbols for averaging of the
signal
• Simulation results: for LOS channel models (residential, office, outdoor), the ranging accuracy is on the order of 0.3 to 0.5 meter. [Assuming uncorrelated errors at both measurements of the round trip delay, 1.4nsec is equivalent to (1-way) distance error of 30cm]
• For NLOS channel models that were presented, the first path delay varies randomly in a certain range, in the model realizations; thus, ranging has a large error in some of the models.For CM=4 (office NLOS – probably a “soft” NLOS model), the std deviation is about 3nsec (0.66m).
• The random arrival of first cluster in the model needs further discussion.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 34
doc.: IEEE 802.15-05-0052-01-004a
Submission
Max Ranging Error Results LOS channel models, N=50 symbols
Max magnitude of Ranging Error in 90% of cases [m]
SNR 10 11.5 13 15 [dB]
CM 1 1.15 0.32 0.32 0.36
CM 3 1.08 1.52 0.69 0.59
CM5 1.15 0.78 0.52 0.34
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 35
doc.: IEEE 802.15-05-0052-01-004a
Submission
Ranging (cont.)
• Considerations for mobile nodes:
• Time for ranging is between 600usec to 1msec.
• For mobility values on the order of 1meter/sec (on a mobile luggage conveyer, for example), the displacement affected while location is measured is negligible – on the order of 0.1 cm. This is also negligible compared to the wave length (~8cm).
• Assuming coherence time requirement of 5ms the maximum doppler rate is ~200Hz, which translates to about 15m/s max speed.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 36
doc.: IEEE 802.15-05-0052-01-004a
Submission
MAC considerations
• Network includes FFD and RFD devices
• Packet structure adheres to 15.4
• Supports the full set of 15.4 MAC functions
• Ranging result – just another parameter transferred from Phy to Mac layer after a single transaction
• Supporting anti-congestion mechanisms at both type of devices.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 37
doc.: IEEE 802.15-05-0052-01-004a
Submission
Receiver Block Diagram
FromAntenna
BPFDown
Conversion +Baseband
Correlator
I
QLNA
LO
Dem odulation+
Acquisition
D ecod ingP acket
hand ling
Hardware
M ay be im plem ented inSoftware
Ranging
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 38
doc.: IEEE 802.15-05-0052-01-004a
Submission
Transmitter Block Diagram
BP F PulseG enerator
To AntennaBarker
Sequencegenerator
T im ing andcontro l
Tx dataC hannel S e lect
PowerAm plifie r
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 39
doc.: IEEE 802.15-05-0052-01-004a
Submission
Technical Feasibility
• The analog (RF) part can be implemented by either SiGe or 0.13u CMOS processes.– The former has a higher bandwidth / more accurate
models for high frequencies– The latter is about 30% lower in cost per mm2.– Both technologies are in use today for similar
frequencies (e.g. 802.11a)– The other high speed elements are also based on
existing technology and modules
• All in all, the die size estimation is 6.3 mm2 (see next slide).
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 40
doc.: IEEE 802.15-05-0052-01-004a
Submission
Estimated Size and Power (RFD)
Estimated
Die Size [mm2 ]
Estimated Power (mW)
Analog Blocks 2.0 2.5
Analog To Digital 0.5 3
Digital Blocks, uP, RAM, ROM 3.3 7.5
Pads 0.5
Total 6.3 13.0
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 41
doc.: IEEE 802.15-05-0052-01-004a
Submission
Power Consumption
• The low power consumption is due to – Activating the components only when a transmission is expected (note the
advantage of a short pulse sequence!)
– Low power consumption design methodologies of all the parts
• Each device typically listens only to the Beacons and rest of time is in sleep mode, thus the effective average power consumption will be reduced by a large factor (e.g. 1%), enabling long battery life
• When in acquisition, a search for a symbol over few hypothesis is made.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 42
doc.: IEEE 802.15-05-0052-01-004a
Submission
Scalability
• Higher (peer to peer) data rates can be achieved by 1. interleaving few packets from same source, which essentially
mean lower separation between consecutive symbols. 2. Using higher order PPM
• For example: Interleaving 10 packets and using 16-ary PPM results in 50Kbps*10*4=2Mbps
• ALL RATES ARE COMPATIBLE AND COEXISTENT!
• Lower (peer to peer) data rates can also be achieved (by using lower coding rates, and increasing preamble length accordingly to accommodate lower SNR), but not recommended
• ‘Hooks’ for a cognitive radio can be added in the future, for example to add programmable notch filters in the transmitter.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 43
doc.: IEEE 802.15-05-0052-01-004a
Submission
Summary
• The Symbol Interleaved Impulse Radio system is a sound, complete system proposal that simultaneously answers all the technical requirements of TG-4a of 802.15 and all minimum SCD criteria
• Offers large advantages Offers large advantages (vs. conventional DS solutions)(vs. conventional DS solutions)
in terms of in terms of RangeRange, , PowerPower, , Aggregate rateAggregate rate and and CostCost
• It enables both a robust design in various channels and scenarios, flexibility to a multitude of applications, and a very low-cost solution
• Good distance performance on most channel models
• We will be happy to cooperate with every one that is interested in this direction, in order to further improve its parameters.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 44
doc.: IEEE 802.15-05-0052-01-004a
Submission
Appendix A: Average and Peak Powers
• Regulation:– Average transmission power is limited to -41.3 dBm/Mhz, or
-14.3dBm for a 500Mhz bandwidth– The peak power per 50Mhz is limited to 0dBm.
• Recall the 11-sequence Barker pulsed transmission (eleven ~2nsec pulses, with 10nsec intervals)
• To achieve the max. Average power, the peak power of each 2nsec pulse will be
-14.3+10*log (20usec/22nsec) = 15dBm
• Now check the peak power measured through a 50Mhz wide filter; it has a time constant of about 20 -30nsec, thus the resultant power is
15 + 10*log (2nsec/10nsec) + 10*log(50/500)= 15-7-10= -2dBm
so that the FCC peak power limit is met.
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 45
doc.: IEEE 802.15-05-0052-01-004a
Submission
Appendix B: Interference Spreadsheet (1)Interferer 802.11.15.3 RemarksCenter freq 2.40 GhzTx power (at its center freq) 20.00 dBmTx ant gain 0.00BW 11.00 Mhz
Tx PSD (out of band)) -41.00 dBm/Mhz 1Path loss at 1meter 44.50 dBEst added loss at 1m distance 0.00 dBRx power -85.50 dBm/Mhz
PSD red in freq 25.00 dB 2Rcvd interf power density -110.50 dBm/Mhz
Proposer Fc 4.00 GhzFreq seperation 1.60 GhzPath loss at 1meter 40.06 dBEst added loss at 1m distance 0.00 dBFilter attenuation of Interf signal 58.00 dB 3Narrow band interf rejection 10.00 dBRx power (from filtered interf sig) -92.50 dBmAvg Rx power (from interf sig, over 500Mhz)) -119.49 dBm/Mhz
Total effective Interf noise density -109.98 dBm/MhzProposer thermal noise level (incl NF) -107 dBm/Mhz
Difference of noise levels 2.98 dBNoise level effective increase 1.77 dBMargin (vs 6dB allowed) 4.23 dB
Remarks1) Probably the actual PSD is lower than the FCC allowed levels2) For a large freq separation, due to finite BW of the Power Amp, power is reduced3) A 3rd order Butterworth Band Pass filter attenuation at 2.4Ghz
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 46
doc.: IEEE 802.15-05-0052-01-004a
Submission
Appendix B: Interference Spreadsheet (2)Interferer 802.11a RemarksCenter freq 5.30 GhzTx power (at its center freq) 15.00 dBmTx ant gain 0.00 dBiBW 16.60 Mhz
Tx PSD (out of band)) -41.00 dBm/Mhz 1Path loss at 1meter 44.50 dBEst added loss at 1m 0.00 dBPSD red in frequency 20.00 dB 2Rx power (from OOB noise) -105.50 dBm/Mhz
Proposer Fc 4.00 GhzFreq seperation -1.30 GhzPath loss at 1 meter 46.94 dBEst added loss at 1m 0.00 dBFilter attenuation of Interf signal 43.00 dB 3Narrow band interf rejection 10.00 dBRx power (from filtered interf sig) -84.94 dBmAvg Rx power (from interf sig, over 500Mhz)) -111.93 dBm/Mhz
Total effective Interf noise density -104.61 dBm/MhzProposer thermal noise level (incl NF) -107 dBm/Mhz
Effective Noise level Increase 4.37 dBMargin (vs. 6dB allowed) 1.63 dB
Remarks1) The actual PSD is typically substantially lower than the FCC allowed levels2) For a large freq separation, due to finite BW of the Power Amp, power is reduced3) For a 3rd order Butterworth band pass filter
January 2005
Dani Raphaeli, Gideon Kaplan (Sandlinks)Slide 47
doc.: IEEE 802.15-05-0052-01-004a
Submission
App. B: Co-Existence Example
Co-Existance Analysis with C-band VsatRemarks
Victim receiver C-band VsatInterferer 802.15.4aCenter freq 4.00 GhzTx power (at its center freq) -14.30 dBmTx ant gain 0.00 dBiBW 500.00 Mhz
Path loss at 1 meter 44.48 dBd 20.00 mAtten of building 10.00 dBTx power at distance d -94.80 dBm
Rcvr center freq 4.00 GhzC-band antenna sidelobe gain -0.53 1Rx power per 36Mhz Transponder -105.70 dBm
DVB-S Receiver sensitivity -91.00 dBm 2
1) Assuming the Vsat Antenna has a 20 deg angle2) See document [15-04-609]