1 / 18

160 MHz PHY Transmission

160 MHz PHY Transmission. Authors:. Date: 2010-05-17. Outline. Motivation Usefulness of 160 MHz PHY transmission mode Contiguous and non-contiguous 160 MHz Coexistence Summary. Motivation (1/2). WLAN continues to provide wireless alternatives to wired LAN 10BASE-T Ethernet: 11a/g

Download Presentation

160 MHz PHY Transmission

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. 160 MHz PHY Transmission Authors: Date: 2010-05-17 Youhan Kim, et al.

  2. Outline • Motivation • Usefulness of 160 MHz PHY transmission mode • Contiguous and non-contiguous 160 MHz • Coexistence • Summary Youhan Kim, et al.

  3. Motivation (1/2) • WLAN continues to provide wireless alternatives to wired LAN • 10BASE-T Ethernet: 11a/g • 100BASE-T Ethernet: 11n • Ability to meet the 1000BASE-T Ethernet throughput (Gigabit wireless) in 11ac would be beneficial • Parallelism with past efforts lends additional legitimacy to 11ac • Could be a clear and simple part of the answer to “what is 11ac?” • Including this capability increases the chance of a major upgrade cycle, and provides better differentiation with previous generation equipments Youhan Kim, et al.

  4. Motivation (2/2) • However, for Gigabit wireless to succeed, it needs to be practical • Achieve 1Gb/s TCP/IP throughput robustly over a reasonable range • Allow wide range of devices, each with different physical limitations (e.g number of antennas), to achieve 1 Gb/s TCP/IP throughput We believe this capability would be instrumental in broader acceptance of 11ac by consumers Youhan Kim, et al.

  5. Usefulness of 160 MHz PHY Transmission • WLAN is becoming prevalent in all types of devices • Different devices have different physical (e.g. number of antenna) limitations • 160 MHz allows even wider range of devices to achieve Gigabit wireless • Opens the door for even more variety of applications * Short GI, 70 % efficiency Youhan Kim, et al.

  6. Benefits of Wide Bandwidth • A wide channel shared among multiple users is more efficient for transporting bursty computer networking data • Modern media codecs use variable bit rates • Wide shared channels are more efficient due to statistical multiplexing • Streams with highly varying bit rate may be more robust with wide channels • Allows sufficient excess BW to meet the peak requirements • Particularly with prioritized QoS • Spectrum that is not used is permanently wasted Youhan Kim, et al.

  7. Contiguous and Non-Contiguous 160 MHz • Contiguous 160 MHz • Transmitted signal consists of a single contiguous frequency spectrum with 160 MHz bandwidth • Non-contiguous 160 MHz • Transmitted signal consists of two frequency segments, each 80 MHz wide • Limit to two non-contiguous segments for reasonable tradeoff between complexity and flexibility WLAN - 160 MHz U-NII 1 U-NII 2 U-NII Worldwide U-NII 3 WLAN - 160 MHz Radar Radar WLAN WLAN 80 MHz WLAN 80 MHz U-NII 1 U-NII 2 U-NII Worldwide U-NII 3 Youhan Kim, et al.

  8. Non-Contiguous 160 MHz • The two frequency segments may be placed in any two 11ac 80 MHz channels • When the two frequency segments are placed next to each other, a non-contiguous 160 MHz device and a contiguous 160 MHz device shall be interoperable • The two frequency segments are used synchronously • Both in TX or both in RX mode • Signal on the two segments are destined to the same receiver(s) WLAN - 160 MHz Radar Radar WLAN WLAN 80 MHz WLAN 80 MHz U-NII 1 U-NII 2 U-NII Worldwide U-NII 3 Youhan Kim, et al.

  9. Contiguous and Non-Contiguous 160 MHz • Contiguous 160 MHz • Suitable for devices with limitation on complexity, area, power, etc. • Non-contiguous 160 MHz • Higher probability of being able to operate in wide bandwidth mode [1] • Able to move around 80 MHz segments to avoid radar and WLAN • Able to utilize U-NII 3 • More effort and cost required to build than contiguous 160 MHz devices • To allow different implementations to independently decide on the tradeoffs between contiguous and non-contiguous operation • Allow 160 MHz devices that support only contiguous 160 MHz operation • 160 MHz devices may optionally support non-contiguous 160 MHz operation as well WLAN - 160 MHz Radar Radar WLAN WLAN 80 MHz WLAN 80 MHz U-NII 1 U-NII 2 U-NII Worldwide U-NII 3 Youhan Kim, et al.

  10. 160 MHz Tone Allocation: Non-Contiguous • Each frequency segment shall follow the 80 MHz tone allocation [2] WLAN - 160 MHz 80 MHz 80 MHz 6 Guard Tones 121 Data/Pilot Tones 3 DC Tones 121 Data/Pilot Tones 5 Guard Tones 6 Guard Tones 121 Data/Pilot Tones 3 DC Tones 121 Data/Pilot Tones 5 Guard Tones Tone Index Tone Index -128 -122 -2 2 122 127 -128 -122 -2 2 122 127 Youhan Kim, et al.

  11. 160 MHz Tone Allocation: Contiguous • Tone allocation equivalent to placing two 80 MHz tone allocations next to each other in frequency • Allows contiguous and non-contiguous 160 MHz devices to interoperate when the two segments of the non-contiguous devices are placed next to each other in frequency • Single PHY rate table for both contiguous and non-contiguous 160 MHz 80 MHz Tone Allocation [2] 80 MHz Tone Allocation [2] 6 Guard Tones 121 Data/Pilot Tones 3 Null Tones 121 Data/Pilot Tones 121 Data/Pilot Tones 3 Null Tones 121 Data/Pilot Tones 5 Guard Tones 11 DC Tones -256 -250 -130 -126 -6 6 126 130 250 255 Subcarrier Index Youhan Kim, et al.

  12. Coexistence • Not as hard as 11n at 2.4GHz • No 11b and Bluetooth • No partially overlapping channels (i.e., 5MHz channel spacing at 2.4GHz) • No limited capabilities of pre-standard 11ac devices (as in 11n) • Various mechanisms may be investigated to ensure coexistence with legacy devices (11a/n) • Some examples of existing 11n mechanisms • Immediate CCA sensing on all BW units • RTS/CTS protection • L-SIG spoofing • Intolerant bit • Some examples of possible new mechanisms • Channel activity profiling on extension channels • More information exchanges between AP and STA on channel profiling • Ability to reserve certain channels for high QoS data Youhan Kim, et al.

  13. Summary • 160 MHz PHY transmission would be a valuable optional feature in 11ac • Allows even wider range of devices to achieve Gigabit wireless • Allow both contiguous and non-contiguous 160 MHz operation • Non-contiguous and contiguous modes shall interoperate when the two 80 MHz non-contiguous segments are placed next to each other • Allow 160 MHz devices that support only contiguous 160 MHz operation • Allow each implementation to independently decide on the tradeoffs between contiguous and non-contiguous operation • Tone allocation for 160 MHz • Contiguous 160 MHz • Equivalent to placing two 80 MHz tone allocations next to each other in frequency • Non-contiguous 160 MHz • Each frequency segment shall employ 80 MHz tone allocation Youhan Kim, et al.

  14. Strawpoll #1 • Do you support adding the following section and item into the specification framework document, 11-09/0992? • Section 3.1.1 160 MHz PHY Transmission • R3.1.1.A: The draft specification shall include support for 160 MHz PHY transmission. • Yes: • No: • Abstain: Youhan Kim, et al.

  15. Strawpoll #2 • Do you support adding the following item into the specification framework document, 11-09/0992? • R3.1.1.B: Tone allocation for 160 MHz operation shall consist of two 80 MHz tone allocations. • Yes: • No: • Abstain: Youhan Kim, et al.

  16. Strawpoll #3 • Do you support adding the following item into the specification framework document, 11-09/0992? • R3.1.1.C: The draft specification shall include support for non-contiguous 160 MHz PHY transmission whose frequency spectrum consists two segments, each transmitted using any two 11ac 80 MHz channels, possibly non-adjacent in frequency. Contiguous and non-contiguous 160 MHz devices shall be capable of transmitting and receiving frames between each other when the two segments of the non-contiguous 160 MHz device are placed in frequency to match the tone allocation of the contiguous 160 MHz device. • Yes: • No: • Abstain: Youhan Kim, et al.

  17. Strawpoll #4 • Do you support adding the following item into the specification framework document, 11-09/0992? • R3.1.1.D: The draft specification shall include support for 160 MHz capable devices that support contiguous operation only. • Yes: • No: • Abstain: Youhan Kim, et al.

  18. References • [1] Cariou, L. and Benko, J., Multichannel transmissions, IEEE 802.11-10/0103r1, Jan. 2010 • [2] Srinivasa, S. et al., 80MHz Tone Allocaiton, IEEE 802.11-10/0370r0, Mar. 2010 Youhan Kim, et al.

More Related