HiperLAN was developed as a wireless local area network standard by ETSI to provide higher data rates than early 802.11 standards. HiperLAN Type 1 achieved data rates up to 2 Mbps for ad hoc networking. HiperLAN Type 2 was later developed to provide connection-oriented service up to 54 Mbps, with quality of service guarantees, security, and flexibility. It uses OFDM in the 5 GHz spectrum for robust transmission. While early products only achieved 25 Mbps, the standard provides a framework for higher speeds as technologies advance. HiperLAN is intended to complement wired networks by providing wireless connectivity in hotspot areas like offices, homes, and public places.

1. HIPERLANHIgh PErformance Radio Local Area Networks www.ustudy.in

3. Local Area Networks (LAN)

4. Bluetooth, 802.11 Family, HiperLAN Family, HomeRF...

5. Wide Area Networks (WAN)

6. GSM, 3G, 4G, Iridium...www.ustudy.in

7. Mobility and data rates for communications standards www.ustudy.in

9. IEEE 802.11 (802.11b, 802.11a, 802.11g...)

10. ETSI HiperLAN (HiperLAN Type 1, Type 2, HiperAccess, HiperLink...)

11. HiperLAN Familywww.ustudy.in

13. Emergence of multimedia applications

14. Demands for high-speed Internet access

15. Deregulation of the telecommunications industrywww.ustudy.in

17. Developed by ETSI during 1991 to 1996

18. Goal: to achieve higher data rate than IEEE 802.11 data rates: 1~2 Mbps, and to be used in ad hoc networking of portable devices

19. Support asynchronous data transfer, carrier-sense multiple access multiple access with collision avoidance (CSMA/CA), no QoS guaranteed.

20. Products

21. Proxim's High Speed RangeLAN5 product family (24Mbps; 5GHz; QoS guaranteed)

22. RadioLAN’s products for indoor wireless communication (10Mbps; 5GHz; Peer-to-Peer Topology)www.ustudy.in

24. Next generation of HiperLAN family: Proposed by ETSI BRAN (Broadband Radio Access Networks) in 1999, and is still under development.

25. Goal: Providing high-speed (raw bit rate ~54Mbps) communications access to different broadband core networks and moving terminals

26. Features: connection-oriented, QoS guaranteed, security mechanism, highly flexibility

27. Product: Prototypes are available now, and commercial products are expected at the end of 2001 (Ericsson).

28. HiperAccess and HiperLink

29. In parallel to developing the HIPERLAN Type 2 standards, ETSI BRAN has started work on standards complementary to HIPERLAN Type 2www.ustudy.in

31. Typical app. Environment: Offices, homes, exhibition halls, airports, train stations, etc.

32. Different with Bluetooth, which is mainly used for linking individual communication devices within the personal area networkwww.ustudy.in

33. www.ustudy.in

35. Generic architecture supporting:Ethernet, IEEE 1394, ATM, 3G etc.

36. Connection-oriented with QoS per conn.

37. Security - authentication & encryption

38. Plug-and-play radio network using DFS

39. Optimal throughput schemewww.ustudy.in

40. Architecture Control Plane User Plane CL MAC ACF DCC RRC EC CAC RLC MAC PHY DLC HiperLAN Type 1 Reference Model PHY HiperLAN Type 2 Reference Model MAC: Medium Access Sub layer EC: Error Control CAC: Channel Access Control Sub layer RLC: Radio Link Control PHY: Physical Layer RRC: Radio Resource Control DLC: Data Link Control Layer ACF: Association Control Function CL: Convergence Layer DCC: DLC Connection Control www.ustudy.in

42. Reference configuration1: information bits 2: scrambled bits 3: encoded bits 4: interleaved bits 5: sub-carrier symbols 6: complex baseband OFDM symbols 7: PHY bursts www.ustudy.in

44. Currently, most WLAN products operate in the unlicensed 2.4GHz band, which has several limitations: 80MHz bandwidth; spread spectrum technology; interference

45. Spectrum allocation for Hiperlan2www.ustudy.in

47. Robustness on highly dispersive channels of multipath fading and intersymbol interference

48. Spectrally efficient

49. Admits great flexibility for different modulation alternatives

50. Facilitated by the efficiency of FFT and IFFT algorithms and DSP chips

51. Hiperlan2: 19 channels (20MHz apart). Each channel divided into 52 subcarrierswww.ustudy.in

53. Key feature: Flexible transmission modes

54. With different coding rates and modulation schemes

55. Modes are selected by link adaptation

56. BPSK, QPSK as well as 16QAM (64QAM) supportedwww.ustudy.in

57. Data Link Control Layer www.ustudy.in

59. Radio resource control function (RRC): handover, dynamic frequency selection, mobile terminal alive/absent, power saving, power control

63. FCH (frequency channel): exact description of the allocation of resources within the current MAC frame

64. ACH (access feedback channel): conveys information on previous attempts at random access

65. Multibeam antennas (sectors) up to 8 beams supported

66. A connection-oriented approach, QoS guaranteedwww.ustudy.in

68. The original request by a MT to send data uses specific time slots that are allocated for random access.

69. AP grants access by allocating specific time slots for a specific duration in transport channels. The MT then sends data without interruption from other MT operating on that frequency.

70. A control channel provides feedback to the sender.www.ustudy.in

72. Repetition mode: typically used for broadcast

74. QoS support: Appropriate error control mode selected; Scheduling performed at MAC level; link adaptation; internal functions (admission, congestion control, and dropping mechanisms) for avoiding overloadwww.ustudy.in

76. There will be a fight between connection and connectionless camps Hiperlan2/802.11a

77. Current products under development and becoming available only offer 25Mbps

78. Hiperlink 155Mbps data rates still some way off

79. Wireless: Useful as an adjunct to the wired worldwww.ustudy.in

80. The End …… Thank You …… www.ustudy.in