Radio-Frequency (RF) and Infrared (IR) are two types of energy used in communicating commands. RF technology uses radio waves to transmit the audio signal, while IR technology is a type of light that can’t be seen by the naked eye, and uses this infrared light to carry the audio signal, allowing the signal to remain in the room.
Radio-Frequency Identification (RFID)
The unidirectionality of radio-frequency
Radio-frequency uses a unidirectional mode of communication, with a simple one-way transmission. The signal from the main station to all electronic shelf labels (ESL) is sent only one-way. Consequently, when a message with information is sent to the ESL, the back-office does not receive any response from the ESL confirming that the message was received.
The creation of dead waves due to interference zones
The radio communication system works with antennas that radiate in a unidirectional way. However, even though their range is greater, and their signal is of better quality, antennas must be carefully arranged to point in a specific direction. When the transmitter or receiver is in motion, communication can be interrupted. In addition, radio waves are not compatible in an environment already cluttered with other wireless networks. There is a great risk of having several dead zones within a store where a large number of ESLs won’t receive the radio signals for price updates.
Long and uncertain price updates
These high interference zones prevent effective communication between the transceivers and the ESLs, but in addition to that, price updates can take several hours to perform. This disruption between the various signals slows down the price automation process. A retailer may then find him/herself having to make price updates overnight. Should the ESLs be updated during the day, customers may be faced with incorrect prices.
A risky system for privacy
According to several media reports, RF energy has raised concerns among consumers in recent years, particularly with regard to privacy.
The concern about the security of consumers’ personal information lies in the risk that detailed product information in store can easily become personally identifiable. In fact, this communication system can associate product data with personal information, since it is collected at each swipe of a credit, debit or loyalty card. As a result, in addition to being able to create a detailed profile of a consumer’s purchasing habits, these concerns are amplified by the fact that a radio ESL can remain activated and thus remain accessible after the purchase.
To ensure fast and efficient operations, radio ESLs need to consume a large amount of energy. Without this very important factor, the transmitter cannot operate at maximum reading range. Consequently, adopting the radio frequency communication system is not an effective way to save energy.
Infrared light (IR)
The bidirectionality of infrared light
Unlike radio-frequency, infrared light has bidirectional communication. The infrastructure of the transceiver allows for both transmitting and receiving all data with the ESLs. For them to function in the store, transmitters are installed on the ceiling. The transmitters communicate information to the ESLs thanks to rapid flashes.
Therefore, when the ESL (equipped with a photo sensor) receives the infrared signal, it will send a message back with a quick flash of light to the back-office to confirm the reception of the new information. In the event that the message is not received, the ESL also sends a notification to the back-office to alert the staff.
As well, the information transmitted by the ESLs is also shared among the transmitters that are intended to communicate with each other.
No dead zones
Even though infrared waves are shorter than radio waves, the strategic placement of transceivers throughout the store (even in hard-to-reach locations) allows for a wide distribution of infrared signals, in addition to establishing a stable two-way communication between the ESLs and the transceivers. Moreover, infrared signals operate above highly congested frequencies of wireless networks such as Wi-Fi. As a result, no interference with other signals is observed.
In fact, infrared technology tends to be used in critical environments such as airplanes, hospitals, or in the retail industry: A sector that requires high reliability, low power consumption and above all, interference-free communication.
Fast, accurate and reliable price updates
Thanks to its ability of remaining unaffected by high-interference areas, infrared light can deliver new information to an electronic shelf label in just seconds. Price changes can then be made day or night, without the risk of customers being faced with incorrect prices.
Moreover, the back-office and transmitters are able to identify which ESL needs updating or encountered an issue. As a result, the system can send a message directly to a specific ESL and not to all the ESLs in-store, thereby saving a large amount of time and energy. However, if necessary, the transmitters can also make broadcasts to all ESLs: A general command that addresses all electronic shelf labels.
A secure communication system
When it comes to security, IR communication only covers a certain perimeter around the transmitters, allowing retailers to have complete control over the waves within the store. Unlike radio waves, which can be listened to or hacked from the outside, infrared signals cannot penetrate walls. As a result, this control guarantees a respect for the consumer’s privacy since IR signals are unable to collect data and retain it. If an ESL responds to a signal, it is in the vicinity of a transmitter that is located inside the store walls.
A robust technology with a long life service
The infrared communication system, by contrast, doesn’t require a large power source for it to operate at full capacity. For retailers, adopting this technology is the most durable solution on the ESL market. With its battery saving technology, the labels can last up to 20 years, and transceivers on the ceiling, several decades once installed. The investment made can be recovered in less than 5 years, as the equipment won’t need to be replaced.
Despite the growth of the wireless radio-frequency system, infrared communication has long dominated electronic shelf label applications which require speed, durability, reliability and advanced functionalities. PRICER’s electronic shelf labels provide this effective and stable communication through the infrared technology which they have been using since 1991.