Murata Manufacturing Co., Ltd. (hereinafter referred to as "Murata") has developed Murata's first (1) "antenna anti-interference device 'Radisol'", which is a new product that can be equipped on antennas to suppress wireless performance degradation. Mass production will begin in June 2024. Mainly used in portable communication products such as wearables and smartphones.
In recent years, smartphones and wearable terminals have begun to be equipped with many wireless communication functions such as Wi Fi, Bluetooth, and GPS, and antennas corresponding to each wireless communication standard have been densely installed to transmit and receive signals. In addition, in order to improve communication quality, MIMO (2) and non terrestrial networks (NTN (3)) that combine multiple antennas are gradually becoming popular, therefore, there is a tendency for the number of antennas equipped in terminals to further increase. If antennas with similar frequency bands are installed at high density, some power that should have radiated into space will interfere with neighboring antennas and flow into them, resulting in a decrease in the radiation characteristics of the antennas. Keeping antennas at a sufficient distance from each other can ensure isolation and prevent interference, but for smartphones and wearable terminals, ensuring space within a narrow casing is very difficult. Therefore, so far, discrete components have been commonly used to form a filter function called energy storage circuit (4) on interfering antennas to suppress interference between antennas. However, there is a problem with this method: due to the insertion loss of the energy storage circuit (5), although the characteristics of the interfered antenna are improved, the antenna characteristics on the side of the energy storage circuit will deteriorate.
Therefore, Murata developed a Radisol that balances high-precision filter characteristics and low insertion loss through unique ceramic multilayer technology and RF circuit design technology. By using Radisol around the antenna, interference between close range antennas can be prevented with lower insertion loss. In addition, Radisol has a small size, which helps to stabilize wireless communication functions in devices such as smartphones and wearable terminals that are equipped with multiple antennas in limited spaces.
This product has been used by Motorola Mobility LLC (headquarters: Libertyville, Illinois, USA, President: Sergio Buniac) for the new smartphone "Edge series" models starting from August 2024. Motorola has improved the performance of its Wi Fi antenna by adopting Radisol.
In the future, Murata will continue to expand Radisol's product lineup according to market demand to cope with more diverse antenna combinations. In addition, Murata will also support the miniaturization of electronic devices and the use of advanced wireless technology, committed to achieving a prosperous and prosperous society.
main features
Optimize antenna characteristics
It is possible to minimize the impact on the antenna passband and take measures to reduce the radiation efficiency caused by interference between antennas.
It can improve antenna efficiency, stabilize wireless communication quality, and reduce device power consumption.
Save space and improve interference between antennas
When using discrete components to implement interference countermeasures, a certain amount of space is required. This product is a small product with a size of 0603, and a single chip can meet the requirements. Therefore, ultra small space can be used to improve interference between antennas.
Main specifications
| product name | Antenna anti-interference device “Radisol” |
|---|---|
| model | LXTS03 |
| size（Typ.) | 0.6mm×0.3mm×0.2mm（0603） |
| attenuation@10Ω（Typ.） | 9～23dB ※Different by variety |
| insertion loss@50Ω（Typ.） | 0.1～0.4dB ※Different by variety |
| Working temperature range | -40～85℃ |
| Input power | 30dBm※ ※A continuous wave, 50 Ω signal source with a duty cycle of 100% |
explanatory note
(1) Murata's investigation results on August 4, 2024
(2) MIMO: The abbreviation for Multi Input Multi Output. The technology of using multiple antennas on both the transmitter and receiver to improve communication quality and speed
(3) NTN: The abbreviation for Non Terrestrial Network. A type of wireless communication network, including mobile communication, refers to a network formed by multi-layer connections between ground base stations, maritime vessels, high-altitude unmanned aerial vehicles (HAPS), and communication satellites deployed in space
(4) Energy storage circuit: A resonant circuit formed by connecting an inductor and a capacitor in parallel. At a specific resonant frequency, it can produce an effect where neither inductors nor capacitors seem to exist. In interference countermeasures, it is used as a band stop filter (BSF) to truncate frequency components within a specific range
(5) Insertion loss: The amount of power lost when a signal passes through a transmission path
