Lyngsoe Systems PT30 Postal Tag, PT30 User Manual PT30 UserManualV3

Lyngsoe Systems Ltd. Postal Tag, PT30 PT30 UserManualV3

User Manual

PT30 Postal Tag RFID-LSCAN Page: 1 of 6 PT30 Postal Tag User Manual Version 3 – Dec 2008
PT30 Postal Tag RFID-LSCAN Page: 2 of 6 TABLE OF CONTENTS 1 INTRODUCTION 3 1.1 Purpose 3 1.2 Definitions 3 2 BLOCK DIAGRAM 3 3 PT30 OPERATION DESCRIPTION 3 3.1 Modes of operation 4 3.2 Valid Excitation Fields 4 3.3 Commands and Parameters 4 3.4 PT23 / PT30 vs. PT21 4 3.4.1 ExId range 4 3.4.2 Black-out 4 4 REGULATORY COMPLIANCE 5 4.1.1 Maximum Transmission Time 5 4.1.2 Maximum Duty Cycle 5
PT30 Postal Tag RFID-LSCAN Page: 3 of 6 1 INTRODUCTION 1.1 Purpose The purpose of this document is to describe the functionality and operation of the PT30 tag intended for use in a RFID system custom designed for International Post Corporation. The tag features reflect the application requirements. You can find more details into “PT30 Functional Specifications”. 1.2 Definitions Valid LF Field – A 125 kHz carrier signal modulated OOK with a signal carrying the exciting device identification number (ExID). Excitation Mode – tag transmits its ID together with the exciter ID when it is woken up by a valid LF field. Transmission – When is excited by a valid LF field, the tag transmits its ID over a 433.92 MHz FSK modulated carrier. 2 BLOCK DIAGRAM Block diagram for Postag PT30 is presented in Figure 2-1 below: 3 PT30 OPERATION DESCRIPTION Postag PT30 is a transponder (RF Tag) that receives an excitation signal and responds by transmitting back a message. It is custom designed for low cost and reliability in the postal environment. It is a direct replacement of previous models PT21 and PT23 tags and can be used with any of the Lyngsoe RFID systems – S96, S21 and S23. Postag PT30 provides the following main functions: - Identifies a valid excitation field and reads the excitation identifier (ExId); - Following a valid excitation, it transmits on 433.92MHz several identical messages that include (among others) the tag user data, the ExId and a battery flag. - Its user data and operating parameters are programmed wirelessly using a special programming device UHF Antenna Figure 2-1
PT30 Postal Tag RFID-LSCAN Page: 4 of 6 3.1 Modes of operation Postag PT30 has several main modes of operation: sleep, LF excitation recognition, UHF transmission and programming. The sleep mode is the normal mode of operation. In the sleep mode, only the LF receiver is powered up and the total current consumption is less than 5uA. When a LF signal is detected by the LF receiver, it wakes-up the microcontroller to check if this signal has a valid modulation pattern. The LF field validation is done by the microcontroller using an RC internal 90 kHz clock at a low current consumption. If a valid excitation field is recognized, then the microcontroller wakes-up its UHF Transmitter and transmits on the UHF the pre-programmed messages. When PT30 recognizes a valid S21 / S23 excitation it transmits on UHF messages using S21 format. The PT30 operation and the message content can be programmed using dedicated devices. The tag transmits a number of messages each time it enters a valid S21 or S23 fields. First transmission is delayed a few ms depending of the parameter WID that programmed randomly for each tag within the 10 -30 range during the manufacturing process. Subsequent transmissions are each randomly delayed compared with the preceding one based on a calculation that involves several random numbers generated internally function of another parameter WSD. This WSD parameter is also programmed randomly for each tag within the 10 -30 range during the manufacturing process. Repeating the same message a number of times ensures that, even if multiple tags are excited in the same time, many messages will not collide and at least one from each tag will be successfully received. 3.2 Valid Excitation Fields For a field to be valid, it has to have a special pattern called exciter ID. If fields with different exciter ID overlap and a tag moves from one to another it will transmit WEP number of messages each time it “sees” a new exciter ID. 3.3 Commands and Parameters The commands and parameters accepted by Postag PT30 are the same as for the Postag PT21 / PT23 and are listed in the RFID System S21 – Reference Guide, document 950061 rev. 1. The most used programmable parameters for PT30 are WIP, WRC and WUD. Examples of default parameters’ values that will fit most applications are: WUD = “xxxxx” 5 characters of user data WIP, WRC= their sum represents the number of identical messages to transmit following an excitation. WIP parameter range is 1 to 20, WRC parameter range is 0 to 10, and default values for each are 10. WID = randomly assigned initial delay after excitation, multiples of 4 ms, range 1-200, default 1. This ensures a randomization of the first transmissions following an (almost) simultaneously excitation of multiple tags. WSD = inter-message random delay, range 7 – 15, default 10 (no direct physical interpretation of this value) 3.4 PT23 / PT30 vs. PT21 The main functional differences between tags model PT23 / PT30 and PT21 are related to the ExId range of identifiers and the black-out time. 3.4.1 ExId range Postags PT21 recognize and report received ExId with S21 format in the range 0 to 31. Postags PT23 / PT30 recognize and report received ExId with S21 format in the range 0 to 31, and with S23 format in the range 0 to 127. 3.4.2 Black-out Black-out is the minimum time interval between two consecutive excitations which the tag can recognize. Postag PT21 has a black-out time 10.0 s. For PT23 and PT30 this blackout time was reduced to less than 2.0 s. In situations where we want to re-register a tag that leaves and re-enters a field with the same exciter ID, the tag has to be out of the field for more than the black out time duration. This happens for example when you try to excite a tag multiple times using the same exciter, like a Universal
PT30 Postal Tag RFID-LSCAN Page: 5 of 6 Programmer UP23 box. If a tag enters LF field but the valid excitation pattern can not be recognized (i.e. overlapping fields or interference), the tag does not transmits anything. 4 REGULATORY COMPLIANCE This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation. This equipment has been tested and found to comply with the limits for Class B digital devices, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instruction manual, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one of more of the following measures: • Reorient or relocate the receiving antenna • Increase the separation between the equipment and receiver • Connect the equipment into an outlet on a circuit different from that to which the receiver is connected. • Consult the dealer or an experienced radio/TV technician for help. Warning: Changes or modifications not expressly approved by the party responsible for compliance could void the user’s authority to operate the equipment. 4.1.1 Maximum Transmission Time To comply with 15.231(a) of FCC regulations, the maximum transmission time of PT30 in Excitation mode must not exceed 5 seconds. To minimize collisions in an application, PT30 tags are programmed with random values for the WSD parameter, which ensures that inter-message durations are randomized differently for individual tags. To ensure sufficient transmission redundancy in an application a certain optimum number of transmitted messages is selected and programmed into the WIP+WRC parameters. The sum of both parameters represents the number of messages transmitted in a burst and this affects the overall transmission duration. In our typical application WIP + WRC = 20 and WSD = 7 and the resulting average transmission time is around 2s. If we set maximum values for these parameters WIP + WRC = 30 and WSD = 30 the resulting transmission time is 4.3s so PT30 still complies with the FCC requirements for maximum transmission time. 4.1.2 Maximum Duty Cycle To comply with 15.231(a) of FCC regulations from average transmitted power point of view, the maximum transmission Duty Cycle for PT30 must not exceed 24% in any 100ms time window. The maximum value of duty cycle in PT30 is achieved when 100ms window falls on the Excitation transmission bursts. The table below shows the best estimate of the duty cycle in 100ms for different combinations of WEP = WIP+WRC and WSD. As we can see as long as WEP = WIP+WRC > 3 and WSD ≥ 7 the duty cycle in any 100ms window varies between 8% and 16% so there is margin compared with the maximum value of 24%.
PT30 Postal Tag RFID-LSCAN Page: 6 of 6 Max Duty Cycle: 20 %Annex 3WSDWEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 401444444444444444444444444444444444444444428888888888888888888888888888888888888888312 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8416 16 16 16 16 16 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8520 20 20 20 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8624 24 24 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8729 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8833 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8933 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 81033 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 81133 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 81233 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 81333 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 81433 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 81533 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 81633 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 81733 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 81833 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 81933 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 82033 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 82133 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 82233 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 82333 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 82433 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 82533 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 82633 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 82733 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 82833 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 82933 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 83033 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 83133 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 83233 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 83333 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 83433 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 83533 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 83633 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 83733 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 83833 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 83933 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 84033 29 29 24 20 20 16 16 16 16 12 12 12 12 12 12 12 12 12 12 12 12 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8Maximum possible Duty Cycle in any 100ms time window during a transmission of one packet of MsgNo messages (set by WBP, WEP, WEB tag parameters).This graph also depends on values of CC and EN parameters set in TagParms form.

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