-[ ] Goals
- [ ] Demonstrate TDMA repeater
- [ ] superior weak signal performance (-135dBm)
- [ ] diversity to handle multipath
- + TDMA diversity, switch rx LO quickly?
- + demo overcoming large fades?
- [ ] wideband audio
- [ ] high bit rate data
- [ ] low cost
- [ ] Full SDR so we can define waveform
- [ ] SSB up and down converters to allow full waveform control
- [ ] no SoCs
-
-[ ] Doc
- [ ] Block diagram
- [ ] Uses cases in paragraph form
- [ ] Gain, NF, IP3 budget spreadsheet
- [ ] Power budget spreadsheet
- [ ] Current per active device
- [ ] Power dissiapation per active device
- [ ] Resistor power dissiapation per active device
- + RF bias currents can be high
-
-[ ] RF Specs
- + these are targets, main goals are functional, leave
- others to get sparkling RF performance
- [ ] spurious tx emissions -45dBC @ 1W
- [ ] IP3 10dBm
- [ ] Blocking 95dB
- [ ] System NF 2dB
- [ ] ACS 50dB,
- [ ] MDS (1200Hz) -135dBm,
- [ ] Tx phase noise -124dBc/Hz ??
-
-
-[ ] Design
- [ ] LNA selected with RF switch
- [ ] switchable power as well
- + as power consumption is so high
- [ ] AGC in rx to facilitate SSB operation
- + a control line from uC DAV/PWM?
- + pump up/down GPIO
- [ ] LO buffer that can be bypassed by DNL
- [ ] put extra 0805/603 compons in parallel for Z matchhing and dnl
- + e.g. on collectors and emitters of RF amps
- [ ] protection for LNA etc if RF switches get set the wrong way
- [ ] xtal filter power
- + limit, how many uW?
- [ ] linear reg for vadc ADC and vref
- + jumper select to test
+Goals
+=====
+
+To demonstrate advanced VHF/UHF Digital Voice features on an open
+software and hardware platform.
+
+[ ] feasibility of "$100" TDMA repeater
+ + show our radio working as a TDMA repeater without a diplexor
+ + temporary mount on hill top, city wide coverage
+ + no split so saves spectrum, potentially low cost (to fill coverage gaps easily)
+[ ] 10dB weak signal performance gain over analog FM and 1st gen DV
+ + "smackdown" video of current state of the art against our solution
+[ ] diversity to handle multipath
+ + TDMA diversity, switch rx LO quickly
+ + demo overcoming large fades
+[ ] wideband audio
+ + for example use 10dB gain to send 10 kbit/s Skype type audio over channel
+[ ] high bit rate data
+ + 10 - 100 kbit/s
+[ ] low cost
+ + several hundred $ sales price
+ + approx $100 BOM
+
+Project Workflow
+================
+
+Manhatten Prototype -> Sch Entry -> PCB Design -> Load and Test -> Demos
+ /\ /\
+ || ||
+ Proto Modem SW Modem SW
+ UI SW
+ Driver SW
+
+Themes
+======
+
++ Full SDR so we can define waveform
++ SSB up and down converters to allow full waveform control
++ no SoCs
++ Demos of advanced DV features is "enough". We don't need
+ sparkling performance in other areas such as all RF specs.
+
+Task List
+=========
+
+
+[ ] Documentation
+ [X] Block diagram
+ [X] Uses cases in paragraph form
+ [X] RF design spreadsheet
+ [X] cascaded Gain
+ [X] cascaded NF
+ [ ] cascaded IP3
+ [ ] Power budget spreadsheet
+ [ ] Current per active device
+ [ ] Power dissipation per active device
+ [ ] Resistor power dissiapation
+ + RF bias currents can be high
+ + don't want to smoke and SM parts
+ [ ] Summary for each rail
+ [ ] Specs
+ + We don't care too much about IP3, Blocking, ACS, tx phase noise,
+ power consumption, they can be modest, equivalent to middle of
+ range VHF radios.
+ + We do care about the following. Check off when demonstrated on
+ prototype of Rev A
+ [X] 12VDC operation
+ [X] NF < 2dB
+ [X] MDS (1200 bit/s 2FSK at BER < 0.03) of < -133dBm
+ [ ] MDS (1200 bit/s 2FSK at BER < 0.03) of < -130dBm (3dB de-sensitisation)
+ with -20dBm blocking signal outside of 144 - 148 MHz
+ [ ] spot check at 88, 108, 150, 200 MHz
+ [ ] 1W tx power with spurious emissions -45dBC
+
+
+[ ] Remaining Manhatten Prototype Tasks
+ + Manhatten Style prototype used to build and test as much as possible
+ [ ] 1W PA
+ [ ] PIN diode TR switch
+ [ ] PA filter
+ [ ] Input (1st) BPF
+ [ ] TDMA switching
+ [ ] how to switch PS rails
+ [ ] tx and rx meet specs
+
[ ] Parts Selection
- [ ] what constitutes a RFC?
- + recc general part
- + current consumption
- + RF characterisistics
- + e.g. for PGA 103 and RF amps
+ + cross off below when part selected and tested in prototype
[ ] New audio amp chip
+ bit better, higher power than LM386
- [ ] should we add a LCD?
- + how would this be used?
- + Could use cheap Nokia 5110, at least in first rev. Well documented and libraried.
[ ] General purpose VHF transistors
+ [ ] General purpose IF transistors
[X] 1st mixer: ADE-1
- [ ] RF switches
+ [X] RF switches
+ Brady has suggest AS17992LF
[ ] 1W PA transistor
[ ] LCD
+ + Could use cheap Nokia 5110, at least in first rev. Well documented and libraried.
[ ] encoder
- [ ] first LO: Si5351
+ [X] first LO: Si5351
+ also 2nd LO
- [ ] optional Si570
+ [X] optional Si570
+ low phase noise soldered in option, provide footprint
+ Si5351 still used as 2nd LO
- [ ] how to select Si570?
- + jumper 0hm resistor?
+ [ ] Prototype parts list to Edwin for review
+ + just major parts, semiconductors
+ + make sure they are obtainable
+ + look for low cost equivalents
+
[ ] Use Cases
+ + need software/test procedure to support the following use cases
+ [ ] test modes
+ + useful for devevelopment and debugging
+ [ ] rx BER
+ + prints BER on LCD when continuous 2FSK/4FSK test frames sent
+ [ ] tx BER
+ + sends continuous test frames using 2FSK/4FSK
[ ] VHF FM radio
- [ ] Open Source VHF DV radio
- [ ] Low MDS
+ [ ] Open Source PTT VHF FreeDV radio
+ + continuous or TDMA? Can they be the same?
[ ] TDMA Repeater
[ ] Diversity rx
+ use 2nd output from 5351
to use, e.g. set a frequency
[ ] Changing waveform
+
[ ] Software Modules
+ + see sm201 Block Diagram page 2
[ ] VHF Modem
+ + cont mode first, we can adpat to burst/TDMA mode next
+ [ ] ideal non-coherent 2FSK/4FSK BER versus Eb/No perf
+ [ ] tracks +/- 500ppm sample clock offsets with no impl loss
+ [ ] +/- 5kHz frequency offset acquisition in 1000ms on continuous signal
+ [ ] C/Octave versions
+ [ ] user defined symbol rate (nominal 1200, 2400), carrier freq, sample rate
+ [ ] can it cope with say 3000 symb/s to allow time for TDMA guard times and sync?
+ + e.g. a gd fit with integerat Fs/Rs ratios
+ + might need TDMA design at same time to answer this question
+ [ ] variable nin style demod C function call, approx 20ms packets
+ [ ] DR to review function headers
+ [ ] automated test script to copare C and Octave units results
+ + to ensure identical implementation
+ [ ] command line ./mfsk_tx and ./mfsk_rx
+ [ ] demo OTA (1200/2400/2FSK/4FSK) using SSB radios or SDR
[ ] VHF protocol
+ + do we need two modes, cont & TDMA?
+ + or is there a way to combine? So one rx does both? Autobaud?
+ + can we optionally use FM friendly machester encoded waveform?
[ ] TDMA framework around modem, burst modem
- [ ] diversity
+ [ ] rx TDMA diversity
+ [ ] test frame tx/rx modes
[ ] New Drivers
[ ] LCD
[ ] Encoder
[ ] Si5351
[ ] UI for setting a frequency
[ ] USB console
+ [ ] USB tx/rx signal streaming
+ [ ] Code to support running Modes
+ [ ] Analog FM
+ [ ] TDMA repeater
+ [ ] Diversity RX
+ [ ] FreeDV PTT TDMA radio
+
[ ] Risks
- + and experiments/tasks/prototypes to mitigate
- [ ] DAC and ADC tied together
- + demo tx/rx switching using this approach
- [ ] Can we use ADE-1 bir-directional?
- + what about diplexor?
- [ ] Investigate use of other mixers
- + but doesnt have to be perfect?
- [ ] Celestra mixer
- [ ] Glens
- [ ] coupled res in shielded box or cots part?
- [ ] how to swithc mixer/xtal filter
- [ ] what else wcould er use instead of NE602?
- [ ] ADC perf
+ + check off when risk has been nailed, e.g. by experiment/test
+ [X] Can we use ADE-1 bir-directional?
+ + yes, use TIA and PIN diode switching
+ [X] coupled res in shielded box or cots part?
+ + make little shields out of blacnk PCB
+ + just make box, doesnt need lids
+ [X] how to switch mixer/xtal filter
+ + tx modulator transistor is part of rx load
+ + alo use of TIA
+ [ ] Is NE602/612 still easy to get?
+ [X] ADC perf
+ SFDR etc, which is why we run it as 100kHz
+ if not good enough we'll need an external ADC
+ test against two tone, MDS and ACR
+ + Result: met 135dBm spec on prototype so OK
[ ] Power dissipation of active devices and resistors
+ easy to exceed limits in SM resistors and transistors
+ RF drivers draw lots of current
- [ ] termination of mixer
+ + mitigation: power spereadhseet in doc section
+ [ ] IF termination of 1st mixer
+ + how to test if this is OK?
[ ] do we need a way to bypass the LNA?
+ or is it OK even with strong signals
+ + mitigation: cascaded IP3 calculations in doc section
+ if this compares to current middle range radios then OK
+ [ ] xtal filter power
+ + what is the limit, how many dBm are we using at the moment?
+ [X] prototype RX works
+ + 1200 bit/s 2FSK at < -133dBm with BER < 0.03
+ + theory with NFis -134dBm at 0.02
+ [ ] prototype TX works
+ + 1200 bit/s 2FSK at 1W spurious -45dBC
+ + demod by SDR at high SNR with 0 BER
+ [ ] TDMA switching
+ + demonstrate design supports tx/rx switching fast enough for TDMA
+
-[ ] PCB layout
+[ ] Sch Entry
+ [ ] linear reg option for vadc ADC and vref
+ + jumper select to test
+ [ ] put extra 0805 or 1206 components in parallel for Z matching and DNL
+ + e.g. on collectors and emitters of RF amps
+ + between building blocks
+ [ ] inductors
+ [ ] coil winding details if air core
+ [ ] tolerance
+ [ ] statement on Q so we know if we can subs SM or need Hi-Q air-core
+ [ ] alignment of coils WRT each other to prevent coupling
+ [ ] location of shields if rqd
+ [ ] how to adjust/if adjustment rqd
+ + e.g. adjust filter by variation in coild spacing against filter spec
+ [ ] 4 by 0.1 inch pin headers in a square pattern to disconnect building blocks
+ [ ] select Si570 with a jumper
+ [ ] review of foot prints for discretes
+ + ease of debug, e.g. if we need to add a LC filter
+ + power handling
+
+[ ] Rev A PCB Layout
+ [ ] footprints for all devices
+ [ ] block diagram showing map of building blocks
+ + separate analog and digital
[ ] shields
[ ] where do we put sheilds
[ ] how to fabricate?
+ + try small pieces of black PCB
[ ] foot prints
[ ] probe points
+ VHF freindly with nearby grounds
+ can we get a 50-ohm probe for cro or spec-an?
So mechanically it can sit on board?
[ ] 50 ohm points for spec an?
- [ ] ways to disconnect modules so we can insert tracking gen and spec an
- + 0805 0 ohm jumpers
+ [ ] 4 pin 0.1 inch headers to disconnect building blocks so we can insert
+ tracking gen and spec an
+
[ ] Manufacture
[ ] is it feasible to have 6 turn coils with one turn taps in production?
[ ] can people wind toroids?
[ ] How will we test and align?
-Unorg notes
------------
-
-What we care about:
-
-+ Software defined waveform (even linear ones like PSK), so must be
- linear up and down conversion, eg. direct FM is out
-+ TDMA so needs a uC with bare metal, no USB and Host PC type devices due
- to latenecies
-+ Functional demos of advanced features
-+ Your idea is you are willing to roll up you sleaves and make it happen.
-
-What we don't care about:
-
-Other people are good the aspects below, we are not. So we focus
-where we can make a difference, like innovateive coding, good modems,
-a new codec, and open source. We are doing enough! Don't have to
-a tick all boxes first time around.
-
-+ minimal cost
-+ your favourite radio architecture - there are many ways to up and down convert a signal.
-+ High RF performance, such as phase noise, blocking, ACR, high tx
- power, multi-band operation, low spurious, component selection, low
- power consumption.
-+ Your favourite chipset
-+ Your idea unless you are willing to roll up you sleeves and make it
- happen.
-+ gold plating - is the feature you are proposing going to add to our
- schedule? Will it introduce risk?
projects / freetel-svn-tracking.git / commitdiff