Antenna Switch Module
View Patent ↗An antenna switch module includes a filter which reduces transmission loss so as to achieve high attenuation in a wide band at harmonic frequencies. This antenna switch module includes the filter, an antenna switch circuit and an adjustment line. The filter passes fundamental frequencies and has an attenuation pole. The antenna switch circuit switches antennas. The adjustment line is connected between the filter and the antenna switch circuit. The adjustment line adjusts its length, and when the filter and the antenna switch circuit are directly connected with each other at a connection point, prevents the impedance when the filter is seen from the connection point and the impedance when the antenna switch circuit is seen from the connection point from becoming complex conjugates of each other at the harmonic frequencies.
1. An antenna switch module comprising:
a filter passing fundamental frequencies and having an attenuation pole, the filter having a first impedance;
an antenna switch circuit switching antennas which match the fundamental frequencies, the antenna switch circuit having a second impedance; and
an adjustment line conductor of a set length connected between the filter and the antenna switch circuit, the set length of the adjustment line conductor adjusting properties at harmonic frequencies of the fundamental frequencies,
wherein when the filter and the antenna switch circuit are connected with each other at a connection point on the adjustment line conductor, the set length of the adjustment line conductor prevents the first impedance and the second impedance from becoming complex conjugates of each other at the harmonic frequencies,
wherein the first impedance and second impedance are measured from the connection point,
wherein a ground layer is divided into a ground layer for the filter and a ground layer for the antenna switch circuit,
wherein the antenna switch module includes a laminated body formed of a plurality of dielectric layers,
wherein the filter is a notch low pass filter.
2. The antenna switch module of claim 1 , wherein
the antenna switch circuit includes an antenna switch element which is a PIN diode.
3. The antenna switch module of claim 2 further comprising:
a coupling line coupled with the adjustment line, wherein
the coupling line and the adjustment line form part of a directional coupler.
4. The antenna switch module of claim 1 , wherein
the antenna switch circuit includes an antenna switch element which is a GaAs switch.
5. The antenna switch module of claim 1 further comprising
a coupling line coupled with the adjustment line, wherein
the coupling line and the adjustment line form part of a directional coupler.
6. An antenna switch module comprising:
a filter passing fundamental frequencies and having an attenuation pole, the filter having a first impedance;
an antenna switch circuit switching antennas which match the fundamental frequencies, the antenna switch circuit having a second impedance; and
an adjustment line conductor of a set length connected between the filter and the antenna switch circuit, the set length of the adjustment line conductor adjusting properties at harmonic frequencies of the fundamental frequencies,
wherein when the filter and the antenna switch circuit are connected with each other at a connection point on the adjustment line conductor, the set length of the adjustment line conductor prevents the first impedance and the second impedance from becoming complex conjugates of each other at the harmonic frequencies,
wherein the first impedance and the second impedance are measured from the connection point,
wherein the filter is a notch low pass filter.
7. The antenna switch module of claim 6 , wherein
the antenna switch circuit includes an antenna switch element which is a PIN diode.
8. The antenna switch module of claim 6 , wherein
a ground layer is divided into a ground layer for the filter and a ground layer for the antenna switch circuit.
9. The antenna switch module of claim 8 , wherein
the antenna switch module includes a laminated body formed of a plurality of dielectric layers.
10. The antenna switch module of claim 6 , wherein
the antenna switch circuit includes an antenna switch element which is a GaAs switch.
11. The antenna switch module of claim 6 further comprising:
a coupling line coupled with the adjustment line,
wherein the coupling line and the adjustment line form part of a directional coupler.