1 / 15

Coexistence Analysis for the 2.4 GHz ISM band

This analysis explores interference in the 2.4 GHz ISM band, discussing the impact on coexistence and performance. It delves into SIR requirements and the effects of interference on different systems like Wi-Fi and Bluetooth. Findings reveal the robustness of PBCC-22 and the challenges posed by OFDM-24 in coexistence scenarios.

mariabaker
Download Presentation

Coexistence Analysis for the 2.4 GHz ISM band

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. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Coexistence Analysis for the 2.4 GHz ISM band Srikanth Gummadi, Sean Coffey, Chris Heegard Home and Office Networking Group, Santa Rosa, CA Kofi Anim-Appiah, Anuj Batra, Matthew B. Shoemake DSP Solutions R&D, Dallas, TX Oren Eliezer Short Distance Wireless Group, Israel Texas Instruments Incorporated Gummadi, et al; Texas Instruments

  2. Outline • Introduction • Simulation Parameters • SIR requirements for coexistence • Performance loss due to interference in AWGN • Conclusions Gummadi, et al; Texas Instruments

  3. Introduction • Coexistence • “To exist together, at the same time, or in the same place” • “To live in peace with another or others despite differences, especially as a matter of policy” • Study of coexistence naturally suggests the following questions: • Q1: How much interference can you withstand? • Q2: How much interference do you cause? Gummadi, et al; Texas Instruments

  4. Time of Arrival for Interferer • Either, the interferer is on the air before a packet is transmitted: • Receiver has knowledge of interference • Interference cancellation techniques can be used • Or, the interferer starts during the payload section of packet • Receiver has no knowledge of interference • Worst case scenario Gummadi, et al; Texas Instruments

  5. Interference Only • Simulation parameters: • Receiver has no knowledge of the interferer • No multipath • No noise • Packet Length • 802.11 systems: 1000 bytes • Bluetooth: DM1/DH1 packet (366 bits) • Performance criteria: • SIR (in dB) required to achieve a PER of 10-2 Gummadi, et al; Texas Instruments

  6. Comparison Matrix – No Noise Comparison Matrix – No Noise Comparison Matrix – No Noise Table shows Signal to Interferer ratio (SIR) in decibels (dB) required for the signal to meet the performance criteria. Gummadi, et al; Texas Instruments

  7. Peak-to-Average Dominates • Interference from PBCC-22 and current Wi-Fi systems have similar effect • OFDM-24 is similar to that of AWGN, which is the worse • PBCC-22 outperforms OFDM-24 in all conditions Gummadi, et al; Texas Instruments

  8. Interference on Bluetooth • Interference from PBCC-22 and current Wi-Fi systems have similar effect • OFDM-24 is a worse interferer on Bluetooth, since it very much resembles AWGN Gummadi, et al; Texas Instruments

  9. Interference on current Wi-Fi Systems • PBCC-22 causes similar interference as current Wi-Fi systems • OFDM-24 is a worse interferer on current Wi-Fi systems Gummadi, et al; Texas Instruments

  10. Interference With Noise • Simulation conditions: • Receiver has no knowledge of the interferer • No multipath • SIR is fixed • Packet Length • 802.11 systems: 1000 bytes • BT: DM1/DH1 (366 bits) • Loss in SNR (in dB) from the AWGN case to achieve a PER of 10-2 • Loss in SNR = SNRfixed SIR - SNRAWGN Gummadi, et al; Texas Instruments

  11. Loss in SNR with SIR = 15 dB Gummadi, et al; Texas Instruments

  12. Loss in SNR with SIR = 10 dB Gummadi, et al; Texas Instruments

  13. Interference From BT • Bluetooth signal has a 20dB bandwidth of 1MHz. • Bluetooth hops over 79 1-MHz wide channels in the 2.4GHz band. Gummadi, et al; Texas Instruments

  14. Interference From BT • Bandwidth required to capture 90% Power: • PBCC22: 12.0 MHz • OFDM24: 15.1 MHz  OFDM gets hits 25% more Gummadi, et al; Texas Instruments

  15. Conclusion • PBCC is more robust than OFDM: • Withstands 6 dB more interference from BT • Withstands 2 dB more interference from current Wi-Fi systems • PBCC causes the same interference as 802.11b: • Coexists with current Wi-Fi systems • Same effect on BT as current systems • OFDM is a worse interferer: Similar to AWGN Gummadi, et al; Texas Instruments

More Related