hero123457/uhd
1
0
Fork 0
mirror of https://github.com/EttusResearch/uhd.git synced 2026-10-25 17:36:10 +00:00
Code Issues Projects Releases Wiki Activity

UBX: Add implementation of TDD xcvr mode and force TX PA on in TDD mode to reduce transient at start of transmission

Browse Source
This commit is contained in:
michael-west 2017-12-05 15:50:12 -08:00
parent 109a2d26b6
commit 7d35f43077
1 changed files with 47 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

59
host/lib/usrp/dboard/db_ubx.cpp
View File

@ -1,5 +1,5 @@
//
// Copyright 2014-15 Ettus Research LLC
// Copyright 2014-17 Ettus Research, A National Instruments Company
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
@ -227,6 +227,8 @@ public:
_iface = get_iface();
dboard_id_t rx_id = get_rx_id();
dboard_id_t tx_id = get_tx_id();
size_t revision = boost::lexical_cast<size_t>(get_rx_eeprom().revision);
_high_isolation = false;
if (rx_id == UBX_PROTO_V3_RX_ID and tx_id == UBX_PROTO_V3_TX_ID) {
_rev = 0;
}
@ -238,6 +240,10 @@ public:
}
else if (rx_id == UBX_V2_40MHZ_RX_ID and tx_id == UBX_V2_40MHZ_TX_ID) {
_rev = 2;
if (revision >= 4)
{
_high_isolation = true;
}
}
else if (rx_id == UBX_V1_160MHZ_RX_ID and tx_id == UBX_V1_160MHZ_TX_ID) {
bw = 160e6;
@ -246,6 +252,10 @@ public:
else if (rx_id == UBX_V2_160MHZ_RX_ID and tx_id == UBX_V2_160MHZ_TX_ID) {
bw = 160e6;
_rev = 2;
if (revision >= 4)
{
_high_isolation = true;
}
}
else if (rx_id == UBX_LP_160MHZ_RX_ID and tx_id == UBX_LP_160MHZ_TX_ID) {
// The LP version behaves and looks like a regular UBX-160 v2
@ -542,6 +552,7 @@ public:
private:
enum power_mode_t {PERFORMANCE,POWERSAVE};
enum xcvr_mode_t {FDX, TDD, TX, RX, FAST_TDD};
/***********************************************************************
* Helper Functions
@ -730,19 +741,20 @@ private:
//validate input
assert_has(ubx_rx_antennas, ant, "ubx rx antenna name");
// Due to an issue with TX path into to the RF switch (U32), there
// is a long transient at the beginning of transmission when the RX
// antenna is set to RX2. Forcing on the TX PA removes the transient,
// so it is forced on only when the RX2 antenna is selected. It is
// cleared when the TX/RX antenna is selected to avoid a higher noise
// floor on RX.
// There can be long transients on TX, so force on the TX PA
// except when in powersave mode (to save power) or on early
// boards that had lower TX-RX isolation when the RX antenna
// is set to TX/RX (to prevent higher noise floor on RX).
// Setting the xcvr_mode to TDD will force on the PA when
// not in powersave mode regardless of the board revision.
if (ant == "TX/RX")
{
set_gpio_field(RX_ANT, 0);
set_cpld_field(TXDRV_FORCEON, 0); // Turn off PA in TDD mode
// Force on TX PA for boards with high isolation or if the user sets the TDD mode
set_cpld_field(TXDRV_FORCEON, (_power_mode == POWERSAVE ? 0 : _high_isolation or _xcvr_mode == TDD ? 1 : 0));
} else {
set_gpio_field(RX_ANT, 1);
set_cpld_field(TXDRV_FORCEON, 1); // Keep PA on
set_cpld_field(TXDRV_FORCEON, (_power_mode == POWERSAVE ? 0 : 1)); // Keep PA on
}
write_gpio();
write_cpld_reg();
@ -1158,7 +1170,7 @@ private:
// Placeholders in case some components need to be forced on to
// reduce settling time. Note that some FORCEON lines are still gated
// by other bits in the CPLD register are are asserted during
// by other bits in the CPLD register and are asserted during
// frequency tuning.
set_cpld_field(RXAMP_FORCEON, 1);
set_cpld_field(RXDEMOD_FORCEON, 1);
@ -1214,7 +1226,29 @@ private:
// The intent is to add behavior based on whether
// the board is in TX, RX, or full duplex mode
// to reduce power consumption and RF noise.
_xcvr_mode = mode;
boost::to_upper(mode);
if (mode == "FDX")
{
_xcvr_mode = FDX;
}
else if (mode == "TDD")
{
_xcvr_mode = TDD;
set_cpld_field(TXDRV_FORCEON, 1);
write_cpld_reg();
}
else if (mode == "TX")
{
_xcvr_mode = TX;
}
else if (mode == "RX")
{
_xcvr_mode = RX;
}
else
{
throw uhd::value_error("invalid xcvr_mode");
}
}
void set_sync_delay(bool is_tx, int64_t value)
@ -1254,12 +1288,13 @@ private:
int _ubx_tx_atten_val;
int _ubx_rx_atten_val;
power_mode_t _power_mode;
std::string _xcvr_mode;
xcvr_mode_t _xcvr_mode;
size_t _rev;
ubx_gpio_reg_t _tx_gpio_reg;
ubx_gpio_reg_t _rx_gpio_reg;
int64_t _tx_sync_delay;
int64_t _rx_sync_delay;
bool _high_isolation;
};
/***********************************************************************