This is the second version of the 4G LTE booster that I've made - an improved version of the first design 4G Booster. Instead of using antenna to transmit the signal to the modem as in the previous designed the second version using SMA to TS6 coaxial connector cable to directly connect to the modem internal antenna.
The new designed is much more efficient and there is no longer the need to put the antenna at certain distance to transmit the signal to 4G modem. And instead direct connect into the modem antenna making the signal 80% efficient with 80% stability.
Components:
1 x 4G Antenna (Input Antenna)
1 x Coupled Inductor 20 mH
1 x 20 Mhz Crystal
3 x 2.5 turns air core inductors
2 x 7.5 turns air core inductors
1 x SMA to TS9 splitter coaxial cable output direct to Modem
Powered by 5 Volt USB
During the day when the 4G traffic are congested due to heavy usage by many active users the signal will fluctuate within the range 3 ~ 4 bars. In the night the signal consistency is much higher especially after 12 midnight as less people are using their phones the signal will stays around 4 bars with 70% consistency.
The construction of this circuit is very cheap probably under $10 USD and you can find the component easily available on eBay. However keep in mind that the crystal oscillator - please get a genuine one from well known manufacturers or from store such DigiKey, Element14, Mouser, RS-Online. I have learned my lesson those crystal made in China is not going to work and in fact you will get around 80% faulty or the frequency precision is not stable.
The reason is very simple with genuine Crystal Oscillator the signal precision is much more efficient and this will keep the stability of the signal produced.
NOTE: There are plenty of 4G signal booster out there made in China but they will work temporarily or not work at all. There are also the one working made in the USA like weBoost, Verizon, T&T booster but they are all expensive.
There is something that I've learned researching on the Microwave UHF signal and the device which capture it like the HuaWei modem. The modem can hold a memory of signal - which means when it goes low and then idle, there is likely the modem will continuously holding low signal until you restart the modem then it will refresh. This behavior maybe vary from one device to another so I can't tell of different devices signal patterns. This memory holding issue can be resolved by restarting the PC and the modem so that fresh signal amplification can reset itself.
4G Booster Circuit | 4G Amplifier Circuit | 4G Signal Booster | 4G Signal Amplifier | LNA Signal Booster | 2.6 Ghz Signal Amplifier | 4G Booster Circuit | Mobile Phone Signal Booster Diagram | 4G Modem di Kuching Sarawak | Best 4G antenna | Most effective cell phone signal antenna
2 weeks ago
can we replace these antennas with microsrtip antenna?
ReplyDeleteYes the fact that i use the antenna is because i don't have the tools to make microstrip antenna.
DeleteHowever using the crystal oscillator would be your early stage experiment. In the final stage you would combine all the circuit such as crystal oscillators, frequency multiplier, frequency mixers, and some germanium diode that you would be your ultimate aim...you can start with the crystal and see the effect first. See some of the link here
1. Crystal oscillator test
2. crystal oscillator with antenna
3. crystal oscillator combine with inductors
4. Ultimate 4G booster with multiple combination
How can 20mhz frequency be used to amplifiy 1900mhz signal?
ReplyDeletenot directly of course there must be a frequency multiplier involved
DeleteThis comment has been removed by the author.
ReplyDeletei am looking for 4g rapeater circuit diagrams .but i clodnt find circuit diagram
ReplyDeleteplease give me 4g repeater circuit diagram
mt whatsapp +94713559310 my email slmkm@yahoo.com
thank you