MULTILAYERED COMPONENTS
Product Details
| Overview |
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The European GSM system is by far the most popular standard for portable phones. It has enabled the spread of dual-band devices using both the 900MHz and 1,800MHz frequency bands (Figure
2). A triple-band device using the 1,900MHz band (PCS in the U.S.) has also been developed. Manufacturers of these terminals are pushing for parts that are both smaller and more
complex. Hitachi Metals is already working to meet these needs, offering 2.0mm x 1.25mm distribution transformers, RF transformers and couplers. Recently developed products include a 2.0mm x 1.25mm low pass filter, diplexer and directional coupler with LPF.
Figure 2. Inside a portable phone 1. Low Pass Filter The low pass filter, connected to the output side of a power amplifier, is used to attenuate the harmonics included in signals generated at double and triple frequencies (Figures 2 and 3). We market two types, for 900MHz and 1,800MHz frequency bands. Figure 3: Electrical Characteristics of Low Pass Filter 2. Diplexer The diplexer is used to separate high and low frequency radio waves in dual-band portable phones. A low pass filter and high pass filter are embedded within the circuit. We have commercialized four types (Figure 4). Figure 4: Electrical Characteristics of Diplexer 3. Directional Coupler with LPF This device, usually connected to the output side of the power amplifier, is used to monitor levels of electrical power transmitted and received and increase and decrease the level in the amplifier through feedback. This product combines with the low pass filter in the coupler to bring size down to 2.0mm x 1.25mm. We are working to reduce these dimensions further to 1.6mm x 0.8mm. |
The European GSM system is by far the most popular standard for portable phones. It has enabled the spread of dual-band devices
- Country:Singapore
- telephone:65-81-3-5765-4075
| The European GSM system is by far the most popular standard for portable phones. It has enabled the spread of dual-band devices |
