中英文文献翻译红外数据协会的一系列红外物理层规则.docx

1、中英文文献翻译红外数据协会的一系列红外物理层规则1.Introduction1.1.ScopeThis physical specificati on is inten ded to facilitate the poi nt-to-poi nt com muni cati on betwee n electr onic devices (e.g., computers and peripherals) using directed half duplex serial in frared com muni cati ons links through free space. This doc

2、ume nt specifies the optical media in terfaces for Serial In frared (SIR) datatransmission up to and including 115.2kbit/s, 0.576 Mbit/s, 1.152Mbit/s, 4.0Mbit/s and 16Mbit/s. It contains specificatio ns for the Active Output In terface and the Active In put In terface, and for the overall li nk. It

3、also contains Appe ndices coveri ng test methods and impleme ntatio n examples.Over the past several years several optical li nk specificati ons have bee n developed. This activity has established the adva ntages of optical in terface specificati ons to defi ne optical li nk parameters n eeded to su

4、pport the defi ned link performa nee. Optical in terface specificatio ns are in depe ndent of tech no logy, apply over the life of the link and are readily testable for con forma nee. The IrDA serial in frared link specificati on supports low cost optoelectr onic tech no logy and is desig ned to sup

5、port a link betwee n two no des from 0 to at least 1 meter apart (20 cm for low power parts: please see Secti on 4.1) as show n in Figure 1 (the two ports n eed not be perfectly alig ned).Node 2Figure 1 Schematic View of the Optical Interface Port Geometry1.2.ReferencesThe following standardseither

6、contain provisions that, through referenee in this text, con stitute provisi ons of this proposed sta ndard, or provide backgro und in formati on. At the time of publication of this document, the editions and dates of the refereneed documents indicated were valid. However, all standards are subject

7、to revision, and parties to agreeme nts based on this proposed sta ndard are en couraged to inv estigate the possibility of applying the most recent editions of the standards listed below.IrDA (I nfrared Data Associati on) Serial In frared Link Access Protocol (IrLAP), Versio n1.1,June 16, 1996.IrDA

8、 (Infrared Data Association) Serial Infrared Link Management Protocol, IrLMP), Versio n 1.1, Jan uary 23, 1996.IrDA (Infrared Data Association) Serial Infrared Physical Layer MeasurementGuideli nes, Versio n 1.0, Jan uary 16, 1998.IrDA (Infrared Data Association) IrMC Specification, Version 1.0.1, J

9、anuary 10, 1998.2.General Description2.1.Point-to-Point Link OverviewThe serial infrared link supports optical link lengths from zero to at least 1 meter with standard power transceivers (20cm for low power transceivers: see section 4.1) for accurate (with in specified bit error ratio), free space c

10、om muni cati on betwee n two in depe ndent no des (such as a calculator and a prin ter, or two computers).2.2.EnvironmentThe Optical In terface Specificati ons apply over the life of the product and over the applicable temperature range for the product. Background light and electric field test con d

11、iti ons are prese nted in Appe ndix A.2.3.Modulation SchemesFor data rates up to and in cludi ng 1.152Mbit/s, RZI modulati on scheme is used, and a“ 0” is represe nted by a light pulse. For rates up to and in clud ing 115o2ks, the optical pulse duration is nominally 3/16 of a bit duration (or 3/16 o

12、f a 115.2kbit/s bit duration).ForO.576Mbit/s and1.152Mbit/s, the optical pulse duration is nominally 1/4 of a bit duratio n.For 4.0Mbit/s, the modulati on scheme is 4PPM .In it, a pair of bits is take n together and called a data symbol. It is divided into 4 “ chips ” , only one of which contains an

13、pulse. For 4.0Mbit/s, the nominal pulse duration (chip duration) is 125 ns. A “1” represe nted by a light pulse.For 16.0Mbi L匕 transmission, the HHH(1, 13) code Qa low duly cycle, rate 2 (d k) (1, 13) runlength limited (RLL) code Zis used as tlic modulation code to achieve thespecified data rate. Th

14、e HHH(1, 13) code guarantees for at least one empty chip and at most 13 empty chips betwee n chips containing pulses in the tran smitted IR sig nal.The 16.0Mbit/s rate packet frame structure is based on the curre nt IrDA-FIR(4.0 Mbit/s) frame format with modifications introduced where necessary to a

15、ccommodate the requirements that are specific to the new modulation code. Furthermore, the HHH(1,13) code is enhan ced with a simple scrambli ng/ descrambli ng scheme to further optimize the duty cycle.3.Media Interface Description3.1.Physical RepresentationA block diagram of one end of a serial inf

16、rared link is shown in Figure 2. Additional sig nal paths may exist. Because there are many impleme ntati on alter natives, this specification only defines the serially encoded optical output and in put sig nals at 3.In the diagram, the electrical signals to the left of the Encoder/Decoder at 1 are

17、serialbit streams. For data rates up to and including 1.152Mbit/s, the optical signals at 3 are bit streams with a 0 being a pulse, and a 1 is a bit period with no pulse. For 4.0Mbit/s, a 4PPM encoding scheme is used, with a “ 1 ” being a pulse and a “ 0”chip with no pulse. For 16.0Mbit/s, a HHH(1,1

18、3), (d,k) = (1,13) run length limited (RLL), low duty cycle, rate 2/3 modulation code is used. The HHH (1,13) code guarantees for at least one empty chip and at most 13 empty chips between chips containing pulses in the transmitted IR signal. A summary of pulse durations for all supported data rates

19、 appears in Table 2 in Section 4.1.The electrical signals at 2 are the electrical analogs of the optical signals at 3. For data rates up to and in clud ing 115.2kbit/s, in additi on to en cod ing, the sig nal at 2 is organized into frames, each byte asynchronous, with a start bit, 8 data bits, and a

20、 stop bit. An impleme ntati on of this (up to 115.2kbit/s) is described in Appe ndix B. For data rates above 115.2kbit/s, data is sent in synchronous frames consisting of many data bytes. Detail of the frame format is found in Section 5.Figure 2. IR Transducer Module3.2.Optical Angle DefinitionsThe

21、optical axis is assumed to be no rmal to the surface of the no des face that contains the optical port (See Figure 3). For convenience, the center of the optical port is taken as the reference point where the optical axis exits the port. If there is asymmetry, as long as the maximum half angle of th

22、e distribution is not greater than the allowable Half-Angle Range maximum, and the minimum half angle of the distribution is not less than the Half-Angle Range minimum, the Half-Angle Range specification is met.4.Media Interface Specifications4.1.Overall LinksThere are two differe nt sets of tran sm

23、itter/receiver specificati ons. The first, referred to as Stan dard, is for a link which operates from 0 to at least 1 meter. The sec on d, referred to as the Low Power Option, has a shorter operating range. There are three possible links (See Table 1 below): Low Power Optio n to Low Power Optio n,

24、Stan dard to Low Power Option; Standard to Standard.The distanceis measuredbetween the optical reference surfaces.Lew Power- Lew PowverStandard - Lw PowerStandard -StandardLink Distance Lwer Limit, meteraD00Minimum Link Distance Upper Limit, meters0.20.310Table 1 Link Distance SpecificationsThe Bit

25、Error Ratio (BER) shall be no greater than 10A-8. The link shall operate and meet the BER specification over its range.Signaling Rate and Pulse Duration An IrDA serial in frared in terface must operate at 9.6kbit/sec ond. Additi onal allowable rates listed below are opti on al. Sig nali ng rate and

26、pulse durati on specificatio ns are show n in Table 2.For all signaling rates up to and including 115.2kbit/s the minimum pulse duration is the same (the specification allows both a 3/16 of bit duration pulse and a minimum pulse duration for the 115.2kbit/s signal (1.63 microseconds minus the 0.22 m

27、icrosecond tolerance). The maximum pulse duration is 3/16 of the bit duration, plus the greater of the tolera nce of 2.5% of the bit durati on, or 0.60 microsec on ds.For 0.576Mbit/s and 1.152Mbit/s, the maximum and minimum pulse durations are the nominal 25% of the bit duration plus 5% (tolerance)

28、and minus 8% (tolerance) of the bit durati on.For 4.0Mbit/s, the maximum and minimum si ngle pulse duratio ns are the nominal 25% of the symbol durati on plus and minus a tolera nce of 2% of the symbol durati on.For 4.0Mbit/s, the maximum and mi nimum double pulse duratio ns are 50% of the symbol pl

29、us and minus a tolera nee of 2% of the symbol durati on. Double pulses may occur whe never two adjace nt chips require a pulse.For 16Mbit/s, the maximum and minimum single pulse durations are the nominal symbol duration plus and minus a tolerance of 8% of the nominal symbol duration.The link must me

30、et the BER specification over the link length range and meet the optical pulse con stra in ts.Signaling RateModulationRate Tolerance % of RatePulse Duration MinimumPulse DurationNomnaiPtilse DurationMaximum2.4 KbltfSR3+7- 0.S71 41 LIS7813 ps88 55 iis9 6 K沁R3+/- 0.S71.41 ps19 53 us22 13 iis19 2kbiVsR

31、ZJ+/- 0 S71.41 LIS9.77 its11.07 lis3&4 kbit/sR3+/- 0 B71.4-1 PS4.S8 its5 96 US57.6 kbit/5R3+/- 0 071.41 两3.2B lis4.34 2115 2 kbit/sRZ1+/- 0 871.41 ps1.63 ilis2.23 卜is.576 Mbit/sRa+/- 0.1295.2 ns434 ns520.8 ns1.152 Mbit/sRa+/- 1147.6 ns217 0 ns260.4 ns4.0 Mbrt/s(single putse)4 PPM+/-0.01115.0 ttS125

32、0 ns135.0 ns(double pulse4 PPM+/-0.01240.0 ns250 0 rte260.0 ns16.D r-.1bit/s+/-0.0138.3 ns41 7 ns450 nsTable 2 Si-ialing Rate and Pulse Duration SpecificationsIn order to guarantee non-disruptive coexistencewith slower (115.2kbit/s and below) systems, once a higher speed (above 115.2kbit/s) connection has bee n established, the higher speed system must emit aSerial