Information about Iso 15693
ISO 15693 is an ISO standard for "Vicinity Cards", i.e. cards which can be read from a greater distance as compared to Proximity cards.
ISO 15693 systems operate at the 13.56 MHz frequency, and offer maximum read distance of 1-1.5 metres.
As the vicinity cards have to operate at a greater distance, the necessary magnetic field is less (0.15 to 5 A/m) than that for a proximity card (1.5 to 7.5 A/m).
The data coding is:
Low 6.62 kbit/s ( fc/2048)
High 26.48 kbit/s ( fc/512)
A logic 0 starts with 8 pulses of 423.75 kHz followed by an unmodulated time of 18.88 µs (256/ fc), a logic 1 is the other way round.
The data frame delimitors are code violations, a start of frame is:
and the end of a frame is:
The data is sent using a Manchester code.
The data rate can be:
Low 6.67 kbit/s ( fc/2032)
High 26.69 kbit/s ( fc/508)
A logic 0 starts with 8 pulses of 423.75 kHz followed by 9 pulses of 484.28 kHz, a logic 1 is the other way round.
The data frame delimitors are code violations, a start of frame is:
and the end of a frame is:
The data is sent using a Manchester code.
ISO 15693 systems operate at the 13.56 MHz frequency, and offer maximum read distance of 1-1.5 metres.
As the vicinity cards have to operate at a greater distance, the necessary magnetic field is less (0.15 to 5 A/m) than that for a proximity card (1.5 to 7.5 A/m).
Communication to the card
Communication from the reader to the card uses an Amplitude Shift Keying with 10% or 100% Modulation index.The data coding is:
- 1 out of 4 pulse position modulation
- 2 bits are coded as the position of a 9.44 µs pause in a 75.52 µs symbol time, giving a bit rate of 26.48 kilobits per second The least-significant bits are sent first.
- 1 out of 256 pulse position modulation
- 8 bits are coded as the position of a 9.44 µs pause in a 4.833 ms symbol time, giving a bit rate of 1.65 kbit/s.
Communication to the reader
The card has two ways to send its data back to the reader:Amplitude Shift Keying
Amplitude Shift Keying 100% modulation index on a 423.75 kHz Subcarrier The data rate can be:Low 6.62 kbit/s ( fc/2048)
High 26.48 kbit/s ( fc/512)
A logic 0 starts with 8 pulses of 423.75 kHz followed by an unmodulated time of 18.88 µs (256/ fc), a logic 1 is the other way round.
The data frame delimitors are code violations, a start of frame is:
- an unmodulated time of 56.64 µs (768/ fc),
- 24 pulses of 423.75 kHz
- a logic 1
and the end of a frame is:
- a logic 0
- 24 pulses of 423.75 kHz
- an unmodulated time of 56.64 µs
The data is sent using a Manchester code.
Frequency Shift Keying
frequency-shift keying by switching between a 423.75 kHz sub carrier (operating frequency divided by 32) and a 484.25 kHz sub carrier (operating frequency divided by 28).The data rate can be:
Low 6.67 kbit/s ( fc/2032)
High 26.69 kbit/s ( fc/508)
A logic 0 starts with 8 pulses of 423.75 kHz followed by 9 pulses of 484.28 kHz, a logic 1 is the other way round.
The data frame delimitors are code violations, a start of frame is:
- 27 pulses of 484.28 kHz
- 24 pulses of 423.75 kHz
- a logic 1
and the end of a frame is:
- a logic 0
- 24 pulses of 423.75 kHz
- 27 pulses of 484.28 kHz
The data is sent using a Manchester code.
External links
International Organization for Standardization (Organisation internationale de normalisation), widely known as ISO, is an international standard-setting body composed of representatives from various national standards organizations.
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Proximity card is a generic name for contactless integrated circuit devices used for security access or payment systems. It can refer to the older 125 kHz devices or the newer 13.56 MHz contactless RFID cards, most commonly known as contactless smartcards.
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FreQuency is a music video game developed by Harmonix and published by SCEI. It was released in November 2001. A sequel, titled Amplitude was released in 2003.
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magnetic field is a field that permeates space and which exerts a magnetic force on moving electric charges and magnetic dipoles. Magnetic fields surround electric currents, magnetic dipoles, and changing electric fields.
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Amplitude-shift keying (ASK) is a form of modulation that represents digital data as variations in the amplitude of a carrier wave.
The amplitude of an analog carrier signal varies in accordance with the bit stream (modulating signal), keeping frequency and phase
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The amplitude of an analog carrier signal varies in accordance with the bit stream (modulating signal), keeping frequency and phase
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The modulation index (or modulation depth) of a modulation scheme describes by how much the modulated variable of the carrier signal varies around its unmodulated level. It is defined differently in each modulation scheme.
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Pulse-position modulation is a form of signal modulation in which M message bits are encoded by transmitting a single pulse in one of possible time-shifts. This is repeated every T seconds, such that the transmitted bit rate is M/T bits per second.
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least significant bit (lsb) is the bit position in a binary integer giving the units value, that is, determining whether the number is even or odd. The lsb is sometimes referred to as the right-most bit
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Amplitude-shift keying (ASK) is a form of modulation that represents digital data as variations in the amplitude of a carrier wave.
The amplitude of an analog carrier signal varies in accordance with the bit stream (modulating signal), keeping frequency and phase
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The amplitude of an analog carrier signal varies in accordance with the bit stream (modulating signal), keeping frequency and phase
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A subcarrier is a separate analog or digital signal carried on a main radio transmission, which carries extra information such as voice or data. More technically, it is an already-modulated signal, which is then modulated into another signal of higher frequency and bandwidth.
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In computer networking, a frame is a data packet of fixed or variable length which has been encoded by a data link layer communications protocol for digital transmission over a node-to-node link.
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In telecommunication, Manchester code (also known as Phase Encoding, or PE) is a line code in which the encoding of each data bit has at least one transition. It is therefore self-clocking, which means that a clock can be recovered from the encoded data.
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Frequency-shift keying (FSK) is a modulation scheme in which digital information is transmitted through discrete frequency changes of a carrier wave. The most common form of frequency shift keying is 2-FSK.
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In computer networking, a frame is a data packet of fixed or variable length which has been encoded by a data link layer communications protocol for digital transmission over a node-to-node link.
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In telecommunication, Manchester code (also known as Phase Encoding, or PE) is a line code in which the encoding of each data bit has at least one transition. It is therefore self-clocking, which means that a clock can be recovered from the encoded data.
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