slide1 l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [DSSS UWB Radio Syste PowerPoint Presentation
Download Presentation
Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [DSSS UWB Radio Syste

Loading in 2 Seconds...

play fullscreen
1 / 11

Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [DSSS UWB Radio Syste - PowerPoint PPT Presentation


  • 295 Views
  • Uploaded on

Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [DSSS UWB Radio System] Date Submitted: [ January 2005 ] Source: [Saeid Safavi and Ismail Lakkis ] Company [Wideband Access, Inc.]

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [DSSS UWB Radio Syste' - victoria


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
slide1

Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)

Submission Title: [DSSS UWB Radio System]

Date Submitted: [January 2005]

Source: [Saeid Safavi and Ismail Lakkis ]

Company [Wideband Access, Inc.]

Address [10225 Barnes Canyon Road, Suite A209, San Diego, CA]

Voice:[858-642-9114], FAX: [858-642-2037], E-Mail:[ssafavi@widebandaccess.com]

Re: [Response to Call for Proposals]

Abstract: [This document describes Wideband Access Inc.’s approach for the TG4a alternate PHY]

Purpose: [Preliminary Proposal for the IEEE802.15.4a Standard]

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.

Safavi &i Lakkis, Wideband Access, Inc.

wideband access inc preliminary proposal for ieee 602 15 4a alternate phy

Wideband Access, Inc.Preliminary Proposal for IEEE 602.15.4a Alternate PHY

DSSS UWB Radio System

Saeid Safavi

&

Ismail Lakkis

Safavi &i Lakkis, Wideband Access, Inc.

proposal summary
Proposal Summary
  • A robust direct sequence spread spectrum radio with large processing gains is proposed.
  • Despite its robustness the radio has a very simple and implementable architecture which is anticipated to support the size, cost and power consumption requirements of the altPHY.
  • Using DSSS, channel coding and a high receiver sensitivity, the system provides extended coverage well beyond 30 m.
  • The radio design supports all of the technical requirements of TG4a.

Safavi &i Lakkis, Wideband Access, Inc.

advantages
Advantages
  • Simple Architecture:
    • Facilitates manufacturability and time to market
  • Low Power Consumption:
    • Low rate ADC
    • CMOS technology
  • Low Cost:
    • Single chip implementation
  • Small Size:
    • Compact architecture
    • Minimal usage of external components
  • Extended Range:
    • Large processing gain
    • Improved receiver sensitivity
    • FEC
  • Resistant to Interference, Multipath and Frequency Offsets
  • Proven Location Awareness Methodology

Safavi &i Lakkis, Wideband Access, Inc.

system block diagram

*

System Block Diagram

(Transmitter)

Information

Bits

1.024 Gcps

Radio Channel

BPSK Mod

&

Channel

Coding

BPF

2 Stage

Spreading

A

1kb/s-1Mb/s

~

4 GHz

(50 ppm)

Integrator

(2nd Despreader)

Channel

Decoding

&

Data

Detection

Recovered

Bits

Integrator

(1st Despreader)

BPF

LNA

ADC

Tb

Differential

Detector

(Receiver)

4 GHz

(50 ppm)

Template

Generator

Safavi &i Lakkis, Wideband Access, Inc.

distinctive radio features
Distinctive Radio Features
  • Data Rates: 1 kb/s to 1Mb/s
  • BW: 1.8 GHz (3.1 – 4.9 GHz)
  • Chip Rate: 1.024 Gcps
  • Local Oscillator Offset: 50 ppm
  • High Processing Gain: 30 dB @ 1 Mb/s to 60 dB @ 1kb/s
  • Link Margin: 3 dB gain over OOK
  • Extended Range: due to large processing gain, low sensitivity and FEC the range is significantly larger than 30 m
  • Robust: robustness against noise and phase reversal errors, and high interference resistance due to large processing gain
  • Low Levels of Interference to other systems: Due to the usage of DSSS with large processing gains
  • Single low-power CMOS chip
  • ADC operation at bit rate (rather than chip rate) and Small SizeADC (1- 2 bit)
  • Simple and Cheap Implementation (no expensive components such as SAW filters, etc.)
  • Wide Dynamic Range
  • High Frequency Efficiency: due to efficient use of frequency within the band
  • Precise Ranging Procedure: based on TOA
  • Simple Signal Acquisition and Synchronization
  • Support of large LO offsets: due to the differential detection Scheme
  • Support of Intra-cell mobility
  • Low Interchip Interference: An excellent code cross-correlation through usage of a subset of Kasami codes

Safavi &i Lakkis, Wideband Access, Inc.

properties of kasami sequences
Properties of Kasami Sequences
  • The small set of Kasami sequences is an optimal set of binary sequences with respect to the Welch Bound
  • For 1 Mbps:
    • Sequence length:1023
    • Number of possible sequences 32
    • Max. Autocorrelation SLL: 33
    • Max. Cross-correlation level: 33
  • For lower data rates a 2nd level of spreading is introduced using the same set of Kasami sequences (further increasing the processing gain)

Safavi &i Lakkis, Wideband Access, Inc.

link budget
Link Budget

Safavi &i Lakkis, Wideband Access, Inc.

coexistence and interference susceptibility
Coexistence and Interference Susceptibility
  • Due to the usage of a simple DSSS scheme with no frequency or time hopping, the interference to the neighboring systems is minimal (resulting in low levels of both instantaneous as well as average interference). satisfying the TG4a’s coexistence requirements
  • DSSS with large processing gain would also ensures robustness against interfering devices, hence a high interference susceptibility.

Safavi &i Lakkis, Wideband Access, Inc.

location strategy
Location Strategy
  • The location strategy is based on Time of Arrival (TOA). This method involves measuring the time of arrival of a known signal from the mobile device at three or more reference nodes.
  • The position can be calculated at the server location based on hyperbolic trilateration. More specifically, the location estimate is derived from the value of the Geometric Time Difference (GTD) between the time of arrivals at each node and a known time reference.

Safavi &i Lakkis, Wideband Access, Inc.

conclusions
Conclusions
  • The DSSS system proposed herein is a simple and implementable radio that through its counter measures against, fading, noise and interference can provide the robustness and extended range (well above 30 m) required by TG4a.
  • The location awareness methodology based on TOA provides a precision ranging capability.
  • This system can be integrated in a compact CMOS chip with minimal external components and hence is a small-size, low-cost device. This combined with the radio robustness and location accuracy can support various 802.15.4a applications.
  • The simplicity and the proven modulation techniques used ensures feasibility and scalability of the radio.
  • FFD’s and RFD’s for different applications can be supported due to the scalability provided by a long range of spreading codes.

Safavi &i Lakkis, Wideband Access, Inc.