- One way traffic only, one device transmits and one devices.
- Communication is unidirectional, as on one way street.
- Ex. Keyboard and traditional monitor. â€¢ E.g. keyboard -> monitor.
- Each station can both, transmit and receive, but not at same time. When one device is sending than other can only receive and vice versa.
- E.g. walkie-talkies
- Both station can transmit and receive simultaneously.
- E.g. Telephone
- Message: The message is the information to be communicated. Popular forms of information include text, numbers, pictures, audio and video.
- Sender: the sender is device that sends the data message. It can be a computer, workstation, telephone handset, video camera, and so on.
- Receiver: The receiver is the device that receives the message. It can be a computer, workstation, telephone handset, video camera, and so on.
- Transmission Medium: The transmission is the physical path by which a message travels from sender to receiver. Ex. twisted pair, coaxial cable, fiber-optic cable, and radio waves.
- Protocol: A protocol is a set of rules that govern data communications. It represents an agreement between the communicating devices
- The object of any RFID system is to carry data in suitable transponders, generally known as tags, and to retrieve data, by machine-readable means, at a suitable time and place to satisfy particular application needs. Data within a tag may provide identification for an item in manufacture, goods in transit, a location, the identity of a vehicle, an animal or individual. By including additional data the prospect is provided for supporting applications through item specific information or instructions immediately available on reading the tag. For example, the colour of paint for a car body entering a paint spray area on the production line, the set-up instructions for a flexible manufacturing cell or the manifest to accompany a shipment of goods.
- A system requires, in addition to tags, a means of reading or interrogating the tags and some means of communicating the data to a host computer or information management system. A system will also include a facility for entering or programming data into the tags, if this is not undertaken at source by the manufacturer. Quite often an antenna is distinguished as if it were a separate part of an RFID system. While its importance justifies the attention it must be seen as a feature that is present in both readers and tags, essential for the communication between the two.
To understand and appreciate the capabilities of RFID systems it is necessary to consider their constituent parts. It is also necessary to consider the data flow requirements that influence the choice of systems and the practicalities of communicating across the air interface. By considering the system components and their function within the data flow chain it is possible to grasp most of the important issues that influence the effective application of RFID. However, it is useful to begin by briefly considering the manner in which wireless communication is achieved, as the techniques involved have an important bearing upon the design of the system components.
Areas of Application for RFID
There Are Two Type Error
Memory Cell Is Useful Concept For EC Student.
* Use *
Cell Will Store Binary Value 1 Or 0 .
There Are Two Signle .
1. Write Signal This Signal Will On When User Want Write Data On Memory(Cell)
2. Read Signal Will On When User Want Read From Memory(Cell).
Types Of Memory Cell
— If a symbol can be stored in a cell without continuous supply of energy, it known as non-volatile cell.
— If the symbol stored in a cell disappears when no energy is supplied, it is known as volatile cell.
— If a symbol is read from a cell its content should not be disturbed. Such a cell is known as non-destructive.
— If the symbol is erased, as a result of reading, is said to be destructive.
— The time taken to read a symbol from a cell is called read time and time taken to write a symbol is writetime.
— If in a memory cell, a symbol is permanently written and can only be read, then it is known as a read-only cell.