Recognition Systems
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Optical Mark Recognition (OMR) |
Detects marks on paper, such as filled-in circles or checkboxes |
School registers, multiple-choice examination papers, barcodes, QR codes |
Fast and efficient data collection, reduces manual entry errors |
Limited to predetermined responses, sensitive to poor marking or smudging |
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Optical Character Recognition (OCR) |
Converts printed or handwritten text into machine-readable text |
Automated Number Plate Recognition (ANPR) systems |
Speeds up data processing reduce human error |
Can struggle with different fonts or handwriting styles, sensitive to image quality |
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Radio Frequency Identification Device (RFID) |
Uses radio frequency signals to transmit data stored on a microchip |
Tracking stock, passports, automobiles, contactless payment |
Fast and efficient data transfer, can be read without a direct line of sight |
Limited read range, can be susceptible to interference or hacking |
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Near Field Communication (NFC) |
Enables short-range wireless communication between devices |
Payment using a smartphone |
Convenient and secure, allows for contactless transactions |
Limited range, compatibility issues with some devices |
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Biometric Recognition |
Identifies individuals based on unique biological traits |
Face, iris, retina, finger, thumb, hand, voice recognition |
Highly secure, difficult to forge or replicate |
Expensive technology, privacy concerns, potential false positives or negatives |
Worked example
As banks reduce the number of branches due to the increased use of online banking systems, improved security of customer data is needed. Many banks are introducing biometric systems to secure customer data.
Explain, using examples, why biometric systems are more effective than other methods of security.
[3]
Max 2 of:
The biometric data is unique to the person [1]
The biometrics cannot be forgotten/stolen/shared like passwords [1]
The person needs to be present to enter the data [1]
Difficult to replicate/forge / fake/duplicate [1]
Award 1 mark for any 2 examples:
Examples: fingerprint/palm print / facial recognition/hand geometry/iris / retina scan/voice [1]
How does RFID work?
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RFID Tags
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RFID stands for Radio Frequency Identification. It refers to a technology that uses radio waves to identify and track objects. This system includes RFID tags, which can be attached to objects and contains information about them
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Components of RFID Tags
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RFID tags consist of an integrated circuit (IC) and an antenna. The IC is responsible for storing and processing information, while the antenna receives and transmits the signal
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Passive RFID Tags
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Passive RFID tags do not have a power supply. They get their power from the electromagnetic energy transmitted by the RFID reader
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When the RFID reader emits radio waves, these waves are picked up by the passive tag's antenna
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The energy from the waves is converted into electrical energy, which powers the IC
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The IC then transmits the stored information back to the reader via the antenna, again using radio waves
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Active RFID Tags
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Unlike passive tags, active RFID tags have their power source, which is usually a battery. This allows them to broadcast a signal to the reader actively, making them more powerful and capable of being read from a greater distance
- Active tags emit a signal which is picked up by the RFID reader. They don't require the reader's signal to activate them, unlike passive tags
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Radio Waves
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Both passive and active RFID systems operate by utilising radio waves for communication
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The RFID reader transmits radio waves, which are captured by the RFID tag's antenna in the case of passive tags, or directly interact with the active tags' signal
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The frequency of these radio waves can vary and is generally divided into low-frequency (LF), high-frequency (HF), and ultra-high-frequency (UHF) RFID systems. The choice of frequency impacts the reading distance, speed of data transfer, and ability to penetrate different materials
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Antennas
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The antennas in the RFID system are crucial for the communication between the tag and the reader
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In passive RFID tags, the antenna receives the signal from the reader, powers the IC, and then transmits the tag's information back to the reader
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In active RFID tags, the antenna is responsible for emitting the signal that carries the tag's information to the reader
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Communication with RFID Reader
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The RFID reader emits radio waves, which are either captured by the passive tag or interact with the active tag's signal. The reader then receives the information transmitted by the tag's IC through the tag's antenna. This information can be used to identify and track the tagged object
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Worked example
A farmer has purchased a computerised feeding system for her goats. A goat has an RFID tag
attached to its ear, which is recognised by the computer. The system uses a passive RFID tag.
a. Describe how the RFID tag can be activated.
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3 of:
The RFID reader sends radio waves / signals to the RFID antenna in the tag [1]
The tag sends radio wave/signal back to the reader [1]
The radio waves move from the tag’s antenna to the microchip [1]
A signal is generated and sent back to the RF system [1]
The RF wave is detected by the reader which interprets the data [1]
The system recognises the goat and therefore gives the correct feed to the animal.
b. Describe how RFID technology will be used to give the correct feed to the animal.
[3]
3 of:
The goat passes the RFID reader [1]
The RFID reader extracts data from the tag [1]
The ID is compared with data stored in the database [1]
The feed for the goat is then selected/identified / read from the database [1]
Exam Tip
- When talking about where data is stored, be specific and don't just say 'in the computer/system'. The example above the data is stored in a database
What is Near Field Communication (NFC)?
It's a technology that allows two devices to communicate when they're very close together, typically within a few centimetres. This is the same tech that allows you to make payments by tapping your phone or card on a payment terminal.
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Two Modes of Operation
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NFC works in two modes - reader/writer mode (for reading tags in NFC posters, for example) and peer-to-peer mode (for exchanging data between two NFC devices)
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Power Source
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NFC devices can be either passive or active. Active devices, like smartphones, can both send and receive data. Passive devices, like NFC tags, don't have their own power source and can only send data when they come close to an active device
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Communication
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Communication between NFC devices happens through radio waves. When two NFC devices get close, one sends radio waves that the other can pick up, allowing them to exchange information
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Usage
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NFC enables payment for things at the shop by tapping a phone on the terminal, share files by bringing two phones close together, and use a phone as a bus or train ticket
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Security
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Because NFC only works over a short range, it's generally secure. But it's always good to be aware that any wireless communication could potentially be intercepted, so it's important to only use NFC for secure transactions with trusted devices
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