On Fri, Feb 22, 2013 at 6:28 PM, joel yabut joel@jointventure.com wrote:
May i know the following specs
- What is the tx and rx isolation of umtrx?
- What is the power output in dbm of your umtrx?
Andrey Sviyazov will comment on this.
- How is the lna on the rx input and is an external lna and bpf
recommended?
For Fairwaves 10W base stations we're developing UmSEL, which has channel filter and an additional LNA. For the use without amplifier you don't need any additional filters or LNAs.
- What is the main advantage of umtrx compared to usrp by ettus?
If you want to use it for GSM, then it's cheaper and gives you dual-channel support.
-- Regards, Alexander Chemeris. CEO, Fairwaves LLC / ООО УмРадио http://fairwaves.ru
Hi Joel.
On Fri, Feb 22, 2013 at 6:28 PM, joel yabut joel@jointventure.com wrote:
May i know the following specs
- What is the tx and rx isolation of umtrx?
Not yet measured and unfortunately there are no info from Lime Micro.
- What is the power output in dbm of your umtrx?
After fixing this issuehttps://code.google.com/p/umtrx/issues/detail?id=41&can=1&colspec=ID%20Type%20Status%20Priority%20Milestone%20Owner%20Summary%20ModifiedI measured + 20 dBm for 900 MHz band and +17 dBm for 1800.
- How is the lna on the rx input and is an external lna and bpf
recommended?
For Fairwaves 10W base stations we're developing UmSEL, which has channel filter and an additional LNA. For the use without amplifier you don't need any additional filters or LNAs.
- What is the main advantage of umtrx compared to usrp by ettus?
If you want to use it for GSM, then it's cheaper and gives you dual-channel support.
-- Regards, Alexander Chemeris. CEO, Fairwaves LLC / ООО УмРадио http://fairwaves.ru
Best regards,
Andrey Sviyazov.
OK. Thank you.
- What is the power output in dbm of your umtrx?
After fixing this issuehttps://code.google.com/p/umtrx/issues/detail?id=41&can=1&colspec=ID%20Type%20Status%20Priority%20Milestone%20Owner%20Summary%20ModifiedI measured + 20 dBm for 900 MHz band and +17 dBm for 1800.
I will be testing this UMTRX with a DCS amp with 10 dBM input. Just to be sure, I just need to adjust attenuation to at least 7 dBM and 8 probably to avoid clipping the RF amp as below:
GSM.Radio.PowerManager.MaxAttenDB 8 GSM.Radio.PowerManager.MinAttenDB 0
Is using an LNA with BPF advisable with your UMTRX?
What is the operating temperature of your UMTRX as I want to make sure the HD case I am using for testing is good enough. I installed a small fan and so far temperature is around 40 deg C.
The LEDs are on the board and I may want to solder some LEDs to monitor status, where on the board can I terminate the power for LEDs?
On Tue, Mar 5, 2013 at 10:16 AM, Andrey Sviyazov andreysviyaz@gmail.comwrote:
Hi Joel.
On Fri, Feb 22, 2013 at 6:28 PM, joel yabut joel@jointventure.com wrote:
May i know the following specs
- What is the tx and rx isolation of umtrx?
Not yet measured and unfortunately there are no info from Lime Micro.
- What is the power output in dbm of your umtrx?
After fixing this issuehttps://code.google.com/p/umtrx/issues/detail?id=41&can=1&colspec=ID%20Type%20Status%20Priority%20Milestone%20Owner%20Summary%20ModifiedI measured + 20 dBm for 900 MHz band and +17 dBm for 1800.
- How is the lna on the rx input and is an external lna and bpf
recommended?
For Fairwaves 10W base stations we're developing UmSEL, which has channel filter and an additional LNA. For the use without amplifier you don't need any additional filters or LNAs.
- What is the main advantage of umtrx compared to usrp by ettus?
If you want to use it for GSM, then it's cheaper and gives you dual-channel support.
-- Regards, Alexander Chemeris. CEO, Fairwaves LLC / ООО УмРадио http://fairwaves.ru
Best regards,
Andrey Sviyazov.
Hi Joel.
- What is the power output in dbm of your umtrx?
After fixing this issuehttps://code.google.com/p/umtrx/issues/detail?id=41&can=1&colspec=ID%20Type%20Status%20Priority%20Milestone%20Owner%20Summary%20ModifiedI measured + 20 dBm for 900 MHz band and +17 dBm for 1800.
I will be testing this UMTRX with a DCS amp with 10 dBM input. Just to be sure, I just need to adjust attenuation to at least 7 dBM and 8 probably to avoid clipping the RF amp as below:
GSM.Radio.PowerManager.MaxAttenDB 8 GSM.Radio.PowerManager.MinAttenDB 0
Please explain more what att do you try to use and what clipping do you mean (may be 1dB gain compression) ? Anyhow, you can easy adjust output signal of UmTRX by using --gain in case of UHD TX control. Also can be used TXVGA2 gain in case of direct LMS registers control via Python scripts.
Is using an LNA with BPF advisable with your UMTRX?
Yes of course. External LNA and duplexer or band pass filter should be used for better NF performance.
What is the operating temperature of your UMTRX as I want to make sure the HD case I am using for testing is good enough. I installed a small fan and so far temperature is around 40 deg C.
You can find on the board FUN2 control IC (U35) MAX6665ASA45http://datasheets.maximintegrated.com/en/ds/MAX6665.pdf . So, at the PCB temperature +45'C FUN2 must start to cooling. And if you do not use FAN2 (or broken) then this IC will switch off UmTRX at temperature 45+30=75'C. Low temperature limit is minus 40'C due to industrial components (is not tested 100% in production).
The LEDs are on the board and I may want to solder some LEDs to monitor status, where on the board can I terminate the power for LEDs?
You can use any DC-DC output higher 2V through current limiting resistor. Pleas refer to datasheet of your LED's type to find proper resistor value.
On Tue, Mar 5, 2013 at 10:16 AM, Andrey Sviyazov andreysviyaz@gmail.comwrote:
Hi Joel.
On Fri, Feb 22, 2013 at 6:28 PM, joel yabut joel@jointventure.com wrote:
May i know the following specs
- What is the tx and rx isolation of umtrx?
Not yet measured and unfortunately there are no info from Lime Micro.
- What is the power output in dbm of your umtrx?
After fixing this issuehttps://code.google.com/p/umtrx/issues/detail?id=41&can=1&colspec=ID%20Type%20Status%20Priority%20Milestone%20Owner%20Summary%20ModifiedI measured + 20 dBm for 900 MHz band and +17 dBm for 1800.
- How is the lna on the rx input and is an external lna and bpf
recommended?
For Fairwaves 10W base stations we're developing UmSEL, which has channel filter and an additional LNA. For the use without amplifier you don't need any additional filters or LNAs.
- What is the main advantage of umtrx compared to usrp by ettus?
If you want to use it for GSM, then it's cheaper and gives you dual-channel support.
-- Regards, Alexander Chemeris. CEO, Fairwaves LLC / ООО УмРадио http://fairwaves.ru
Best regards,
Andrey Sviyazov.
-- Mother Ignacia Avenue corner Scout Rallos St. Quezon City, Metro Manila, Philippines
Best regards, Andrey Sviyazov.
Yes i need to attenuate the tx output and Also take into consideration the 1 db compression. I just have to min attenuation to 8.
Sent from my Ipad
On Mar 11, 2013, at 3:20 AM, Andrey Sviyazov andreysviyaz@gmail.com wrote:
Hi Joel.
- What is the power output in dbm of your umtrx?
After fixing this issue I measured + 20 dBm for 900 MHz band and +17 dBm for 1800.
I will be testing this UMTRX with a DCS amp with 10 dBM input. Just to be sure, I just need to adjust attenuation to at least 7 dBM and 8 probably to avoid clipping the RF amp as below:
GSM.Radio.PowerManager.MaxAttenDB 8 GSM.Radio.PowerManager.MinAttenDB 0
Please explain more what att do you try to use and what clipping do you mean (may be 1dB gain compression) ? Anyhow, you can easy adjust output signal of UmTRX by using --gain in case of UHD TX control. Also can be used TXVGA2 gain in case of direct LMS registers control via Python scripts.
Is using an LNA with BPF advisable with your UMTRX? Yes of course. External LNA and duplexer or band pass filter should be used for better NF performance.
What is the operating temperature of your UMTRX as I want to make sure the HD case I am using for testing is good enough. I installed a small fan and so far temperature is around 40 deg C.
You can find on the board FUN2 control IC (U35) MAX6665ASA45. So, at the PCB temperature +45'C FUN2 must start to cooling. And if you do not use FAN2 (or broken) then this IC will switch off UmTRX at temperature 45+30=75'C. Low temperature limit is minus 40'C due to industrial components (is not tested 100% in production).
The LEDs are on the board and I may want to solder some LEDs to monitor status, where on the board can I terminate the power for LEDs?
You can use any DC-DC output higher 2V through current limiting resistor. Pleas refer to datasheet of your LED's type to find proper resistor value.
On Tue, Mar 5, 2013 at 10:16 AM, Andrey Sviyazov andreysviyaz@gmail.com wrote: Hi Joel.
On Fri, Feb 22, 2013 at 6:28 PM, joel yabut joel@jointventure.com wrote:
May i know the following specs
- What is the tx and rx isolation of umtrx?
Not yet measured and unfortunately there are no info from Lime Micro.
- What is the power output in dbm of your umtrx?
After fixing this issue I measured + 20 dBm for 900 MHz band and +17 dBm for 1800.
- How is the lna on the rx input and is an external lna and bpf
recommended?
For Fairwaves 10W base stations we're developing UmSEL, which has channel filter and an additional LNA. For the use without amplifier you don't need any additional filters or LNAs.
- What is the main advantage of umtrx compared to usrp by ettus?
If you want to use it for GSM, then it's cheaper and gives you dual-channel support.
-- Regards, Alexander Chemeris. CEO, Fairwaves LLC / ООО УмРадио http://fairwaves.ru
Best regards, Andrey Sviyazov.
-- Mother Ignacia Avenue corner Scout Rallos St. Quezon City, Metro Manila, Philippines
Best regards, Andrey Sviyazov.
Joel,
In addition to comments from Andrey:
On Sun, Mar 10, 2013 at 10:00 PM, joel yabut joel@jointventure.com wrote:
I will be testing this UMTRX with a DCS amp with 10 dBM input. Just to be sure, I just need to adjust attenuation to at least 7 dBM and 8 probably to avoid clipping the RF amp as below:
GSM.Radio.PowerManager.MaxAttenDB 8 GSM.Radio.PowerManager.MinAttenDB 0
Yes, you could use these config values to control power output. Note, that maximum output power is control by MinAttenDB and not MaxAttenDB, because these are attenuation values.
Is using an LNA with BPF advisable with your UMTRX?
It depends on you intended usage. For high power BTS you need them, yes. At this moment we're designing a proper RF solution for UmTRX as a part of our UmSITE hardware.
What is the operating temperature of your UMTRX as I want to make sure the HD case I am using for testing is good enough. I installed a small fan and so far temperature is around 40 deg C.
It is designed to meet industrial temperature range, but only units used for UmSITE will be tested during manufacturing. UmTRX's which are sold as DIY kit are not tested and could be assumed to meet indoor temperature range.
The LEDs are on the board and I may want to solder some LEDs to monitor status, where on the board can I terminate the power for LEDs?
You could use "Ext connector" or LED1/LED2/LED3 connectors. Please check schematics for details.
-- Regards, Alexander Chemeris. CEO, Fairwaves LLC / ООО УмРадио http://fairwaves.ru
I have a question about the ideal RSSI Noise. I am testing the UMTRX and have the following obeservation:
when I type noise with the default setup of RX GAin 47. the RSSI noise is -26dB and when i change the noise to RX Gain 0. the RSSI noise goes down to -46dB.
Which is the better option? as I understand the lower the noise floor the better. Now if I install my Duplexer, LNA and BPF my noise goise up to -16dB. Is this okay or should I trim the RX gain? What is the ideal RSSI NOISE?
Thanks, Joel
On Tue, Mar 5, 2013 at 10:07 PM, Alexander Chemeris < alexander.chemeris@gmail.com> wrote:
On Fri, Feb 22, 2013 at 6:28 PM, joel yabut joel@jointventure.com wrote:
May i know the following specs
- What is the tx and rx isolation of umtrx?
- What is the power output in dbm of your umtrx?
Andrey Sviyazov will comment on this.
- How is the lna on the rx input and is an external lna and bpf
recommended?
For Fairwaves 10W base stations we're developing UmSEL, which has channel filter and an additional LNA. For the use without amplifier you don't need any additional filters or LNAs.
- What is the main advantage of umtrx compared to usrp by ettus?
If you want to use it for GSM, then it's cheaper and gives you dual-channel support.
-- Regards, Alexander Chemeris. CEO, Fairwaves LLC / ООО УмРадио http://fairwaves.ru
Joel,
On Wed, Mar 13, 2013 at 9:09 PM, joel yabut joel@jointventure.com wrote:
I have a question about the ideal RSSI Noise. I am testing the UMTRX and have the following obeservation:
when I type noise with the default setup of RX GAin 47. the RSSI noise is -26dB and when i change the noise to RX Gain 0. the RSSI noise goes down to -46dB.
Which is the better option? as I understand the lower the noise floor the better. Now if I install my Duplexer, LNA and BPF my noise goise up to -16dB. Is this okay or should I trim the RX gain? What is the ideal RSSI NOISE?
I can't give you an easy answer here. We're using a complicated procedure of tuning Rx gain to specific hardware configuration of our base stations. If you don't have measurement equipment, you could follow this manual to get to working results: https://code.google.com/p/umtrx/wiki/RunningOpenBTS#Tune_OpenBTS_for_specifi...
-- Regards, Alexander Chemeris. CEO, Fairwaves LLC / ООО УмРадио http://fairwaves.ru
Thanks I have done this already. I have a spectrum analyzer as well but I am just want to check if I really need to install the LNA as it seems that noise is going up.
Joel,
What matters is not an absolute noise level, but signal SNR.
On Mon, Mar 18, 2013 at 10:52 PM, Joel Que Yabut Joel@jointventure.com wrote:
Thanks I have done this already. I have a spectrum analyzer as well but I am just want to check if I really need to install the LNA as it seems that noise is going up.
-- Joint Venture SLEC, Inc.
No. 2 Scout Rallos, Quezon City, Metro Manila Philippines Tel. 63 2 3742969 Fax 63 2 3748662
On 3/19/13 2:49 AM, "Alexander Chemeris" alexander.chemeris@gmail.com wrote:
Joel,
On Wed, Mar 13, 2013 at 9:09 PM, joel yabut joel@jointventure.com wrote:
I have a question about the ideal RSSI Noise. I am testing the UMTRX and have the following obeservation:
when I type noise with the default setup of RX GAin 47. the RSSI noise is -26dB and when i change the noise to RX Gain 0. the RSSI noise goes down to -46dB.
Which is the better option? as I understand the lower the noise floor the better. Now if I install my Duplexer, LNA and BPF my noise goise up to -16dB. Is this okay or should I trim the RX gain? What is the ideal RSSI NOISE?
I can't give you an easy answer here. We're using a complicated procedure of tuning Rx gain to specific hardware configuration of our base stations. If you don't have measurement equipment, you could follow this manual to get to working results: https://code.google.com/p/umtrx/wiki/RunningOpenBTS#Tune_OpenBTS_for_speci fic_hardware
-- Regards, Alexander Chemeris. CEO, Fairwaves LLC / ООО УмРадио http://fairwaves.ru
-- Regards, Alexander Chemeris. CEO, Fairwaves LLC / ООО УмРадио http://fairwaves.ru
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Alexander Chemeris -
Andrey Sviyazov -
Joel Que Yabut -
joel yabut
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Joel Yabut