#+TITLE:       readme

* software
** gqrx
http://gqrx.dk/download/install-ubuntu

** gnu radio
sudo apt install gnuradio
sudo apt install gr-osmosdr

** baudline
http://www.baudline.com/download.html

* [[https://ranous.files.wordpress.com/2018/02/rtl-sdr4linux_quickstartv2-18.pdf][RTL-SDR for Linux QuickStart Guide]]

* setup
sample rate 1.8M
at zoom 1.0, display bandwidth is 463360K - 461600K = 1760K (pretty close to sample rate)
strong signal at 462.362M and weaker one at 462.463M

* decoding
** fsk
[[https://nccgroup.github.io/RFTM/fsk_receiver.html][Developing an FSK receiver step-by-step]]
block diagram: https://nccgroup.github.io/RFTM/images/grc_demod_save.png

[[https://blog.habets.se/2017/04/Decoding-FSK.html][Decoding FSK]]

https://stackoverflow.com/questions/36898574/fsk-demodulation-with-gnu-radio
https://www.ripublication.com/ijeer17/ijeerv9n8_03.pdf
** Lora
[[https://www.youtube.com/watch?v=NoquBA7IMNc][Decoding the LoRa PHY (33c3)]]
** rtl-amr
https://github.com/bemasher/rtlamr
Hey, rtlamr author here.  The command front and center in the article
is misleading. rtlamr doesn’t support multiple protocols
simultaneously, specifying -msgtype more than once in the same
invocation has undefined behavior. I would guess that msgtype will
have the value provided in the first flag use.

I should also note that K-roy and I have really bad timing. I few days
ago I released a companion utility to rtlamr for collecting and
aggregating IDM packets from rtlamr into InfluxDB. To solve
essentially the same problem it looks like he put a lot of effort into
solving.

rtlamr-collect handles duplicate messages using IntervalCount and
TransmitTimeOffset given in each IDM so that only new data is stored.
https://github.com/bemasher/rtlamr-collect

https://hackaday.com/2017/12/21/read-home-power-meters-with-rtl-sdr/
https://blog.kroy.io/monitoring-home-power-consumption-for-less-than-25/

[[https://www.youtube.com/watch?v=lkEfJkDTQIQ][Using RTL-SDR to read values from wireless electric/gas/water meters]]

* meter info
** https://www.aclara.com/wp-content/uploads/2014/11/3000-Gas-MTU.pdf

** http://12160.info/profiles/blogs/pge-smart-meters-base-frequency-462-4125-mhz

** [[https://www.reddit.com/r/amateurradio/comments/17kav1/aclara_hexagram_mtus_for_remote_water_meter/][aclara_hexagram_mtus_for_remote_water_meter]]
The transmission to DCU lasts 70 ms, sends the last 10 readings, has a
CRC that the DCU verifies and is unencrypted

Default configuration is to transmit 4 times a day

Possible modulation based on the FCC test: "For purposes of this test,
the transmitter was FSK modulated with a continuous sequence of
Manchester encoded 1’s at the specified 1200 bits per second data
rate. The Manchester encoding scheme forces a mid-bit transition for
an encoded “1”. Therefore, the sequence of continuous 1’s sends the
highest frequency waveform to the modulator circuit."
** patent US8441372B2: Wireless broadband communications network for a utility
[[https://patents.google.com/patent/US8441372B2/en?q=(ami+fsk)&assignee=aclara&oq=(ami+fsk)+assignee:aclara]]
The transmission frequency between each node and its associated DCU
is, for example, 450 MHz. Data transmission is done, for example,
using a frequency shift keying (FSK) modulation technique. Using an
underlying frequency of 450 MHz, and a channel spacing of, for
example, 12.5 KHz, FSK allows a baud rate of up to approximately 1200
baud.
** patent US5903231A: System for encoding base N data using a multi-level coding scheme
[[https://patents.google.com/patent/US5903231A/en?q=(fsk)&assignee=aclara&oq=(fsk)+assignee:aclara]]
** my meter
[[https://lh3.googleusercontent.com/I459R1vy9O8eLkgVCPSH0THCBQuegvwx4iBasFJSrstWscYLFPMKvIBikS0x253iU11ZpBRFpzbfwNnlnX6nqgZjK-qsTZoY_BnawxC9Cmn1YEcZIyhzDSkiSnm0CKjXsIAX--3woEhLhe7CGchoqhge18QilQXevhBS6fMiIyBXFn6_ZEv1_u5aww9VxXwhRzlniaVGsmc5Ux_ugjyCMBx__BLbGe81RjwsILBkKYdbI70Gwmscuq86QcY8dcwPI-ZLNx2ue3ttyxeFoP7AkyPmjN1mI9V89DNjVxzqzEq9nAjDuTYp_BNR6IYs3e8ia2teveeqWsmU0bFRoQH0iWUH135R2bLdeLtdA491914px14IQim8PsiI8xiQ_05NU7Z9yJDWBTrxO1RX3Ybe0B_zXi2HkfyrAdwkk2BGncNKd6K_kx0c-IesIRVp33L0GIJsI_w9iWkpTztWAG5Phamh3356LbuW5qHlYo7xJlaGxOGYAoWS5OoiL2H3IBL_KCz4AJYtzgNTBwGLJUw3RDVUYK4DN5MpkOotN5t6E-KS5MFJ94W62ClK-wjhZ2S8ZWfwqu6GcPJT_Vx5e0pQp2btmWSEqqKwPJJbi3oz5jV_7SUzGVVEGUNTvq46mSIgjgDxHrS5y9V2u2j54CpifC7z3g=w1267-h950-nooelec][image of my meter]]
MTU ID # 30361526 (0x1CF47B6)
462.4125 MHz 462412500 Hz
Single Input MTU 7712AM
Star Hexagram
https://patents.google.com/patent/US5719564A/en - Utility meter reading system
https://patents.google.com/patent/US5617084A/en - Apparatus for communicating utility usage-related information from a utility usage location to a utility usage registering device
** other strong signal attic 462.3625Mhz
* other resources
https://www.reddit.com/r/RTLSDR/comments/82a72a/how_to_read_pge_gas_meter_with_rtlsdr/

https://www.sigidwiki.com/wiki/Signal_Identification_Guide
https://www.sigidwiki.com/wiki/FLEX

https://github.com/EliasOenal/multimon-ng

https://www.discriminator.nl/pdw/index-en.html

Universal Radio Hacker: investigate wireless protocols like a boss
https://github.com/jopohl/urh#linux