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authorjcorgan <jcorgan@221aa14e-8319-0410-a670-987f0aec2ac5>2008-12-31 22:19:48 +0000
committerjcorgan <jcorgan@221aa14e-8319-0410-a670-987f0aec2ac5>2008-12-31 22:19:48 +0000
commit5eb35d758f7bf08b821479d11a8784689eef239c (patch)
tree5746da92ca312c4615b81503ef24f822e21d2a8a
parentbe2af97adb04146243019b5d3eb8bc44ca44e1a4 (diff)
For USRP2, implement auto scaling of TX pipeline such that [-1.0 1.0] input to
usrp2.sink_32fc results in full-scale DAC outputs, regardless of interpolation rate. git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@10182 221aa14e-8319-0410-a670-987f0aec2ac5
Diffstat
-rw-r--r--gr-usrp2/src/usrp2.i13
-rw-r--r--gr-usrp2/src/usrp2_sink_base.cc6
-rw-r--r--gr-usrp2/src/usrp2_sink_base.h5
-rw-r--r--usrp2/host/include/usrp2/usrp2.h5
-rw-r--r--usrp2/host/lib/usrp2.cc6
-rw-r--r--usrp2/host/lib/usrp2_impl.cc37
-rw-r--r--usrp2/host/lib/usrp2_impl.h1
7 files changed, 67 insertions, 6 deletions
diff --git a/gr-usrp2/src/usrp2.i b/gr-usrp2/src/usrp2.i
index e85de20823..28944e6761 100644
--- a/gr-usrp2/src/usrp2.i
+++ b/gr-usrp2/src/usrp2.i
@@ -137,6 +137,8 @@ public:
bool set_interp(int interp_factor);
bool set_scale_iq(int scale_i, int scale_q);
int interp();
+ %rename(_real_default_tx_scale_iq) default_scale_iq;
+ void default_scale_iq(int interp, int *scale_i, int *scale_q);
%rename(_real_dac_rate) dac_rate;
bool dac_rate(long *rate);
double gain_min();
@@ -257,7 +259,7 @@ def __freq_range(self):
self.freq_max()]
def __daughterboard_id(self):
- dbid = make_int_ptr();
+ dbid = make_int_ptr()
r = self._real_daughterboard_id(dbid)
if r:
result = deref_int_ptr(dbid)
@@ -266,6 +268,12 @@ def __daughterboard_id(self):
free_int_ptr(dbid)
return result
+def __default_tx_scale_iq(self, interp):
+ scale_i = make_int_ptr()
+ scale_q = make_int_ptr()
+ self._real_default_tx_scale_iq(interp, scale_i, scale_q)
+ return (deref_int_ptr(scale_i), deref_int_ptr(scale_q))
+
usrp2_source_32fc_sptr.set_center_freq = __set_center_freq
usrp2_source_16sc_sptr.set_center_freq = __set_center_freq
usrp2_sink_32fc_sptr.set_center_freq = __set_center_freq
@@ -296,4 +304,7 @@ usrp2_source_16sc_sptr.daughterboard_id = __daughterboard_id
usrp2_sink_32fc_sptr.daughterboard_id = __daughterboard_id
usrp2_sink_16sc_sptr.daughterboard_id = __daughterboard_id
+usrp2_sink_32fc_sptr.default_scale_iq = __default_tx_scale_iq
+usrp2_sink_16sc_sptr.default_scale_iq = __default_tx_scale_iq
+
%}
diff --git a/gr-usrp2/src/usrp2_sink_base.cc b/gr-usrp2/src/usrp2_sink_base.cc
index c04914eedf..579aaaa4c5 100644
--- a/gr-usrp2/src/usrp2_sink_base.cc
+++ b/gr-usrp2/src/usrp2_sink_base.cc
@@ -64,6 +64,12 @@ usrp2_sink_base::set_interp(int interp_factor)
return d_u2->set_tx_interp(interp_factor);
}
+void
+usrp2_sink_base::default_scale_iq(int interp_factor, int *scale_i, int *scale_q)
+{
+ return d_u2->default_tx_scale_iq(interp_factor, scale_i, scale_q);
+}
+
bool
usrp2_sink_base::set_scale_iq(int scale_i, int scale_q)
{
diff --git a/gr-usrp2/src/usrp2_sink_base.h b/gr-usrp2/src/usrp2_sink_base.h
index 0c4fe72c66..fad965623a 100644
--- a/gr-usrp2/src/usrp2_sink_base.h
+++ b/gr-usrp2/src/usrp2_sink_base.h
@@ -56,6 +56,11 @@ public:
bool set_interp(int interp_factor);
/*!
+ * \brief Calculate default scale_iq for given interpolation factor
+ */
+ void default_scale_iq(int interpolation_factor, int *scale_i, int *scale_q);
+
+ /*!
* \brief Set transmit IQ scale factors
*/
bool set_scale_iq(int scale_i, int scale_q);
diff --git a/usrp2/host/include/usrp2/usrp2.h b/usrp2/host/include/usrp2/usrp2.h
index 82b1c6449f..39da63aa5d 100644
--- a/usrp2/host/include/usrp2/usrp2.h
+++ b/usrp2/host/include/usrp2/usrp2.h
@@ -219,6 +219,11 @@ namespace usrp2 {
//! Return current interpolation factor
int tx_interp();
+ /*
+ * \brief Calculate default scale_iq for given interpolation rate
+ */
+ void default_tx_scale_iq(int interpolation_factor, int *scale_i, int *scale_q);
+
/*!
* Set transmit IQ magnitude scaling
*/
diff --git a/usrp2/host/lib/usrp2.cc b/usrp2/host/lib/usrp2.cc
index 2a7fe5963a..90a31b2205 100644
--- a/usrp2/host/lib/usrp2.cc
+++ b/usrp2/host/lib/usrp2.cc
@@ -309,6 +309,12 @@ namespace usrp2 {
return d_impl->tx_interp();
}
+ void
+ usrp2::default_tx_scale_iq(int interpolation_factor, int *scale_i, int *scale_q)
+ {
+ d_impl->default_tx_scale_iq(interpolation_factor, scale_i, scale_q);
+ }
+
bool
usrp2::set_tx_scale_iq(int scale_i, int scale_q)
{
diff --git a/usrp2/host/lib/usrp2_impl.cc b/usrp2/host/lib/usrp2_impl.cc
index 04f50f4804..2aa4301383 100644
--- a/usrp2/host/lib/usrp2_impl.cc
+++ b/usrp2/host/lib/usrp2_impl.cc
@@ -46,7 +46,6 @@
#endif
static const int DEFAULT_RX_SCALE = 1024;
-static const int DEFAULT_TX_SCALE = 3000;
namespace usrp2 {
@@ -187,9 +186,6 @@ namespace usrp2 {
// set workable defaults for scaling
if (!set_rx_scale_iq(DEFAULT_RX_SCALE, DEFAULT_RX_SCALE))
std::cerr << "usrp2::ctor set_rx_scale_iq failed\n";
-
- if (!set_tx_scale_iq(DEFAULT_TX_SCALE, DEFAULT_TX_SCALE))
- std::cerr << "usrp2::ctor set_tx_scale_iq failed\n";
}
usrp2::impl::~impl()
@@ -768,11 +764,42 @@ namespace usrp2 {
return false;
bool success = (ntohx(reply.ok) == 1);
- if (success)
+ if (success) {
d_tx_interp = interpolation_factor;
+
+ // Auto-set TX scaling based on interpolation rate
+ int scale_i, scale_q;
+ default_tx_scale_iq(d_tx_interp, &scale_i, &scale_q);
+ return set_tx_scale_iq(scale_i, scale_q);
+ }
+
return success;
}
+ void
+ usrp2::impl::default_tx_scale_iq(int interpolation_factor, int *scale_i, int *scale_q)
+ {
+ // Calculate CIC interpolation (i.e., without halfband interpolators)
+ int i = interpolation_factor;
+ if (i > 128)
+ i = i >> 1;
+ if (i > 128)
+ i = i >> 1;
+
+ // Calculate dsp_core_tx gain absent scale multipliers
+ float gain = (1.65*i*i*i)/(4096*pow(2, ceil(log2(i*i*i))));
+
+ // Calculate closest multiplier constant to reverse gain
+ int scale = (int)rint(1.0/gain);
+ // fprintf(stderr, "if=%i i=%i gain=%f scale=%i\n", interpolation_factor, i, gain, scale);
+
+ // Both I and Q are identical in this case
+ if (scale_i)
+ *scale_i = scale;
+ if (scale_q)
+ *scale_q = scale;
+ }
+
bool
usrp2::impl::set_tx_scale_iq(int scale_i, int scale_q)
{
diff --git a/usrp2/host/lib/usrp2_impl.h b/usrp2/host/lib/usrp2_impl.h
index 0400a108b8..b332d65d26 100644
--- a/usrp2/host/lib/usrp2_impl.h
+++ b/usrp2/host/lib/usrp2_impl.h
@@ -146,6 +146,7 @@ namespace usrp2 {
double tx_freq_max() { return d_tx_db_info.freq_max; }
bool set_tx_interp(int interpolation_factor);
int tx_interp() { return d_tx_interp; }
+ void default_tx_scale_iq(int interpolation_factor, int *scale_i, int *scale_q);
bool set_tx_scale_iq(int scale_i, int scale_q);
bool tx_32fc(unsigned int channel,
generated by cgit v1.2.3 (git 2.39.1) at 2025-03-24 22:25:32 +0000