Passive Tag Transmission in Class 1:
5.2. Reader-Tag Half-Duplex Communication
As specified in Section 6, the Reader-to-Tag and Tag-to-Reader communication occurs in a half-duplex manner. The Reader initiates communication by modulating a complete command. The Reader then transmits an unmodulated continuous wave (CW) signal. The Tag modulates its reflection of the CW signal (backscatter communication).
5.3. Reader-to-Tag Communication Signals
A Reader may emit no signals at any frequency, may emit a CW signal at a single frequency, or may emit a modulated signal at a single frequency.
5.3.1. Reader-to-Tag Signal Modulation Depth
The Reader communicates with tags using Amplitude Shift Keying (ASK) with a minimum modulation depth of 30% and a maximum modulation depth of 100%. Modulation shape, depth and rate of modulation are variable within the limits described below. Compliant Tags will adjust their timing over a range of modulation rates to lock to reader transmissions automatically during the [CLKSYNC] period of a Reader command.
Have read Class 1 Gen2 specification, draft the pesudo-code framework using Java. Thinking about a whether a discrete simulation is necessary, and the means of performance measurement.
In implement simulation of Gen2, a simplification is made in message transmission, like ACK and Session selection etc., which have no influence in the anti-collision measurement so far.
Session selection deals with Reader-to-Reader collision.
ACK is reliable transmission and for further processing in tag.
Showing posts with label EPCGlobal Class 1. Show all posts
Showing posts with label EPCGlobal Class 1. Show all posts
Wednesday, December 05, 2007
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