MOBILE COMMUNICATION CIRCUITRY FOR THREE OR MORE ANTENNAS
Communication circuitry is disclosed that is capable of switching between three or more antennas while providing low harmonic interference during carrier aggregation. In one embodiment, a communication system includes a first switch with two poles and four throws, a second switch with two poles and four throws, and four diplexers associated with four antennas. In a second embodiment, the communication system includes a first switch with three poles and three throws, a second switch with three poles and three throws, and three diplexers associated with three antennas. In the second embodiment, the second switch may have a third pole associated with non-cellular signals such as GPS and WiFi, and one or more of the diplexers may be tunable, for example to efficiently pass 1.575 GHz for GPS signals.
1 . A communication system for at least three antennas, the communication system comprising:
a first switch configured to communicate with a main low band signal at a first pole of the first switch and to communicate with a second low band signal at a second pole of the first switch;
a second switch configured to communicate with a main high band signal at a first pole of the second switch and to communicate with a second high band signal at a second pole of the second switch;
a first diplexer configured to communicate with a first antenna;
a second diplexer configured to communicate with a second antenna;
a third diplexer configured to communicate with a third antenna; and
wherein the first switch includes a first throw of the first switch in communication with the first diplexer, a second throw of the first switch in communication with the second diplexer, and a third throw of the first switch in communication with the third diplexer, and
wherein the second switch includes a first throw of the second switch in communication with the first diplexer, a second throw of the second switch in communication with the second diplexer, and a third throw of the second switch in communication with the third diplexer.
2 . The communication system of claim 1 , further comprising:
a control system configured to control the first switch and the second switch.
3 . The communication system of claim 1 , wherein the first diplexer is tunable and includes a low pass section and a high pass section.
4 . The communication system of claim 3 , further comprising:
a control system configured to tune the first diplexer as a function of frequency of operation to minimize insertion losses.
5 . The communication system of claim 3 , further comprising:
a control system configured to tune a stop band zero in the low pass section of the first diplexer to provide attenuation at a second harmonic of the main low band signal or the second low band signal during transmission.
6 . The communication system of claim 3 , further comprising:
a control system configured to tune a stop band zero in the low pass section of the first diplexer to provide attenuation at a third harmonic of the main low band signal or the second low band signal during transmission.
7 . The communication system of claim 1 , wherein the second switch is further configured to communicate with a non-cellular signal at a third pole of the second switch.
8 . The communication system of claim 7 , further comprising:
a control system configured to control the switches and diplexers to: transmit or receive the main high band signal through the first antenna; receive a diversity signal through the second antenna; and transmit or receive a WiFi signal through the third antenna.
9 . The communication system of claim 7 , wherein the third diplexer is tunable and includes a low pass section and a high pass section, and the communication system further comprising:
a control system configured to control the switches and diplexers to: transmit or receive the main high band signal through the first antenna; receive a diversity signal through the second antenna; receive a GPS signal through the third antenna; and tune the high pass section of the third diplexer to pass the GPS signal with low losses.
10 . The communication system of claim 7 , wherein the first switch is further configured to communicate with the non-cellular signal at a third pole of the first switch.
11 . A communication system for at least four antennas, the communication system comprising:
a first switch configured to communicate with a main low band signal at a first pole of the first switch and to communicate with a second low band signal at a second pole of the first switch;
a second switch configured to communicate with a main high band signal at a first pole of the second switch and to communicate with a second high band signal at a second pole of the second switch;
a first diplexer configured to communicate with a first antenna;
a second diplexer configured to communicate with a second antenna;
a third diplexer configured to communicate with a third antenna;
a fourth diplexer configured to communicate with a fourth antenna; and
wherein the first switch includes a first throw of the first switch in communication with the first diplexer, a second throw of the first switch in communication with the second diplexer, a third throw of the first switch in communication with the third diplexer, and a fourth throw of the first switch in communication with the fourth diplexer;
wherein the second switch includes a first throw of the second switch in communication with the first diplexer, a second throw of the second switch in communication with the second diplexer, a third throw of the second switch in communication with the third diplexer, and a fourth throw of the second switch in communication with the fourth diplexer.
12 . The communication system of claim 11 , further comprising:
a control system configured to control the first switch and the second switch.
13 . The communication system of claim 11 , wherein the first diplexer is tunable and includes a low pass section and a high pass section.
14 . The communication system of claim 13 , further comprising:
a control system configured to tune the first diplexer as a function of frequency of operation to minimize insertion losses.
15 . The communication system of claim 13 , further comprising:
a control system configured to tune a stop band zero in the low pass section of the first diplexer to provide attenuation at a second harmonic of the main low band signal or the second low band signal during transmission.
16 . The communication system of claim 13 , further comprising:
a control system configured to tune a stop band zero in the low pass section of the first diplexer to provide attenuation at a third harmonic of the main low band signal or the second low band signal during transmission.
17 . The communication system of claim 11 , wherein the second switch is further configured to communicate with a non-cellular signal at a third pole of the second switch.
18 . The communication system of claim 17 , further comprising:
a control system configured to control the switches and diplexers to: transmit or receive the main high band signal through the first antenna; receive a diversity signal through the second antenna; and transmit or receive a WiFi signal through the third antenna.
19 . The communication system of claim 17 , wherein the third diplexer is tunable and includes a low pass section and a high pass section, and the communication system further comprising:
a control system configured to control the switches and diplexers to: transmit or receive the main high band signal through the first antenna; receive a diversity signal through the second antenna; receive a GPS signal through the third antenna; and tune the high pass section of the third diplexer to pass the GPS signal with low losses.
20 . The communication system of claim 17 , wherein the first switch is further configured to communicate with a non-cellular signal at a third pole of the first switch.
21 . The communication system of claim 7 , wherein the third diplexer is tunable and includes a low pass section having a first bandpass response centered in a low pass band and a high pass section having a second bandpass response centered in a middle/high pass band, and the communication system further comprising:
a control system configured to control the switches and diplexers to: transmit or receive the main high band signal through the first antenna; receive a diversity signal through the second antenna; receive a GPS signal through the third antenna; and tune the high pass section of the third diplexer to pass the GPS signal with low losses.
22 . The communication system of claim 21 , wherein the third diplexer includes a shunt inductor configured to attenuate very low frequency blockers and configured to tune the low pass section into a band pass.
23 . The communication system of 22 , wherein the third diplexer further includes a low pass filter in the high pass section configured to attenuate 5 GHz ISM (Industrial Scientific and Medical) band blockers.
24 . The communication system of claim 1 , wherein the third diplexer is tunable and includes a first tunable bandpass section and a second tunable bandpass section.