GNU Radio Manual and C++ API Reference 3.10.5.1
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gr::digital::clock_recovery_mm_cc Class Referenceabstract

Mueller and Müller (M&M) based clock recovery block with complex input, complex output. More...

#include <gnuradio/digital/clock_recovery_mm_cc.h>

Public Types

typedef std::shared_ptr< clock_recovery_mm_ccsptr
 
- Public Types inherited from gr::block
enum  work_return_t { WORK_CALLED_PRODUCE = -2 , WORK_DONE = -1 }
 Magic return values from general_work. More...
 
enum  tag_propagation_policy_t { TPP_DONT = 0 , TPP_ALL_TO_ALL = 1 , TPP_ONE_TO_ONE = 2 , TPP_CUSTOM = 3 }
 enum to represent different tag propagation policies. More...
 

Public Member Functions

virtual float mu () const =0
 
virtual float omega () const =0
 
virtual float gain_mu () const =0
 
virtual float gain_omega () const =0
 
virtual void set_verbose (bool verbose)=0
 
virtual void set_gain_mu (float gain_mu)=0
 
virtual void set_gain_omega (float gain_omega)=0
 
virtual void set_mu (float mu)=0
 
virtual void set_omega (float omega)=0
 
- Public Member Functions inherited from gr::block
 ~block () override
 
unsigned history () const
 
void set_history (unsigned history)
 
void declare_sample_delay (int which, unsigned delay)
 
void declare_sample_delay (unsigned delay)
 
unsigned sample_delay (int which) const
 
bool fixed_rate () const
 Return true if this block has a fixed input to output rate. More...
 
virtual void forecast (int noutput_items, gr_vector_int &ninput_items_required)
 Estimate input requirements given output request. More...
 
virtual int general_work (int noutput_items, gr_vector_int &ninput_items, gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
 compute output items from input items More...
 
virtual bool start ()
 Called to enable drivers, etc for i/o devices. More...
 
virtual bool stop ()
 Called to disable drivers, etc for i/o devices. More...
 
void set_output_multiple (int multiple)
 Constrain the noutput_items argument passed to forecast and general_work. More...
 
int output_multiple () const
 
bool output_multiple_set () const
 
void set_alignment (int multiple)
 Constrains buffers to work on a set item alignment (for SIMD) More...
 
int alignment () const
 
void set_unaligned (int na)
 
int unaligned () const
 
void set_is_unaligned (bool u)
 
bool is_unaligned () const
 
void consume (int which_input, int how_many_items)
 Tell the scheduler how_many_items of input stream which_input were consumed. More...
 
void consume_each (int how_many_items)
 Tell the scheduler how_many_items were consumed on each input stream. More...
 
void produce (int which_output, int how_many_items)
 Tell the scheduler how_many_items were produced on output stream which_output. More...
 
void set_relative_rate (double relative_rate)
 Set the approximate output rate / input rate. More...
 
void set_inverse_relative_rate (double inverse_relative_rate)
 Set the approximate output rate / input rate using its reciprocal. More...
 
void set_relative_rate (uint64_t interpolation, uint64_t decimation)
 Set the approximate output rate / input rate as an integer ratio. More...
 
double relative_rate () const
 return the approximate output rate / input rate More...
 
uint64_t relative_rate_i () const
 return the numerator, or interpolation rate, of the approximate output rate / input rate More...
 
uint64_t relative_rate_d () const
 return the denominator, or decimation rate, of the approximate output rate / input rate More...
 
mpq_class & mp_relative_rate ()
 return a reference to the multiple precision rational representation of the approximate output rate / input rate More...
 
virtual int fixed_rate_ninput_to_noutput (int ninput)
 Given ninput samples, return number of output samples that will be produced. N.B. this is only defined if fixed_rate returns true. Generally speaking, you don't need to override this. More...
 
virtual int fixed_rate_noutput_to_ninput (int noutput)
 Given noutput samples, return number of input samples required to produce noutput. N.B. this is only defined if fixed_rate returns true. Generally speaking, you don't need to override this. More...
 
uint64_t nitems_read (unsigned int which_input)
 Return the number of items read on input stream which_input. More...
 
uint64_t nitems_written (unsigned int which_output)
 Return the number of items written on output stream which_output. More...
 
tag_propagation_policy_t tag_propagation_policy ()
 Asks for the policy used by the scheduler to moved tags downstream. More...
 
void set_tag_propagation_policy (tag_propagation_policy_t p)
 Set the policy by the scheduler to determine how tags are moved downstream. More...
 
int min_noutput_items () const
 Return the minimum number of output items this block can produce during a call to work. More...
 
void set_min_noutput_items (int m)
 Set the minimum number of output items this block can produce during a call to work. More...
 
int max_noutput_items ()
 Return the maximum number of output items this block will handle during a call to work. More...
 
void set_max_noutput_items (int m)
 Set the maximum number of output items this block will handle during a call to work. More...
 
void unset_max_noutput_items ()
 Clear the switch for using the max_noutput_items value of this block. More...
 
bool is_set_max_noutput_items ()
 Ask the block if the flag is or is not set to use the internal value of max_noutput_items during a call to work. More...
 
void expand_minmax_buffer (int port)
 
long max_output_buffer (size_t i)
 Returns max buffer size on output port i. More...
 
void set_max_output_buffer (long max_output_buffer)
 Request limit on max buffer size on all output ports. More...
 
void set_max_output_buffer (int port, long max_output_buffer)
 Request limit on max buffer size on output port port. More...
 
long min_output_buffer (size_t i)
 Returns min buffer size on output port i. More...
 
void set_min_output_buffer (long min_output_buffer)
 Request limit on the minimum buffer size on all output ports. More...
 
void set_min_output_buffer (int port, long min_output_buffer)
 Request limit on min buffer size on output port port. More...
 
void set_blkd_input_timer_value (unsigned int timer_value_ms)
 DEPRECATED Configure the timer set when input is blocked port. More...
 
unsigned int blkd_input_timer_value ()
 DEPRECATED Returns timer value set when input is blocked. More...
 
void allocate_detail (int ninputs, int noutputs, const std::vector< int > &downstream_max_nitems_vec, const std::vector< uint64_t > &downstream_lcm_nitems_vec, const std::vector< uint32_t > &downstream_max_out_mult_vec)
 Allocate the block_detail and necessary output buffers for this block. More...
 
buffer_sptr replace_buffer (size_t src_port, size_t dst_port, block_sptr block_owner)
 Replace the block's buffer with a new one owned by the block_owner parameter. More...
 
float pc_noutput_items ()
 Gets instantaneous noutput_items performance counter. More...
 
float pc_noutput_items_avg ()
 Gets average noutput_items performance counter. More...
 
float pc_noutput_items_var ()
 Gets variance of noutput_items performance counter. More...
 
float pc_nproduced ()
 Gets instantaneous num items produced performance counter. More...
 
float pc_nproduced_avg ()
 Gets average num items produced performance counter. More...
 
float pc_nproduced_var ()
 Gets variance of num items produced performance counter. More...
 
float pc_input_buffers_full (int which)
 Gets instantaneous fullness of which input buffer. More...
 
float pc_input_buffers_full_avg (int which)
 Gets average fullness of which input buffer. More...
 
float pc_input_buffers_full_var (int which)
 Gets variance of fullness of which input buffer. More...
 
std::vector< float > pc_input_buffers_full ()
 Gets instantaneous fullness of all input buffers. More...
 
std::vector< float > pc_input_buffers_full_avg ()
 Gets average fullness of all input buffers. More...
 
std::vector< float > pc_input_buffers_full_var ()
 Gets variance of fullness of all input buffers. More...
 
float pc_output_buffers_full (int which)
 Gets instantaneous fullness of which output buffer. More...
 
float pc_output_buffers_full_avg (int which)
 Gets average fullness of which output buffer. More...
 
float pc_output_buffers_full_var (int which)
 Gets variance of fullness of which output buffer. More...
 
std::vector< float > pc_output_buffers_full ()
 Gets instantaneous fullness of all output buffers. More...
 
std::vector< float > pc_output_buffers_full_avg ()
 Gets average fullness of all output buffers. More...
 
std::vector< float > pc_output_buffers_full_var ()
 Gets variance of fullness of all output buffers. More...
 
float pc_work_time ()
 Gets instantaneous clock cycles spent in work. More...
 
float pc_work_time_avg ()
 Gets average clock cycles spent in work. More...
 
float pc_work_time_var ()
 Gets average clock cycles spent in work. More...
 
float pc_work_time_total ()
 Gets total clock cycles spent in work. More...
 
float pc_throughput_avg ()
 Gets average throughput. More...
 
void reset_perf_counters ()
 Resets the performance counters. More...
 
void setup_pc_rpc ()
 Sets up export of perf. counters to ControlPort. Only called by the scheduler. More...
 
bool is_pc_rpc_set () const
 Checks if this block is already exporting perf. counters to ControlPort. More...
 
void no_pc_rpc ()
 If the block calls this in its constructor, it's perf. counters will not be exported. More...
 
void set_processor_affinity (const std::vector< int > &mask) override
 Set the thread's affinity to processor core n. More...
 
void unset_processor_affinity () override
 Remove processor affinity to a specific core. More...
 
std::vector< int > processor_affinity () override
 Get the current processor affinity. More...
 
int active_thread_priority ()
 Get the current thread priority in use. More...
 
int thread_priority ()
 Get the current thread priority stored. More...
 
int set_thread_priority (int priority)
 Set the current thread priority. More...
 
bool update_rate () const
 
void system_handler (pmt::pmt_t msg)
 the system message handler More...
 
void set_log_level (const std::string &level) override
 Set the logger's output level. More...
 
std::string log_level () override
 Get the logger's output level. More...
 
bool finished ()
 returns true when execution has completed due to a message connection More...
 
block_detail_sptr detail () const
 
void set_detail (block_detail_sptr detail)
 
void notify_msg_neighbors ()
 Tell msg neighbors we are finished. More...
 
void clear_finished ()
 Make sure we don't think we are finished. More...
 
std::string identifier () const
 
- Public Member Functions inherited from gr::basic_block
pmt::pmt_t message_subscribers (pmt::pmt_t port)
 
 ~basic_block () override
 
long unique_id () const
 
long symbolic_id () const
 
std::string name () const
 
std::string symbol_name () const
 
std::string identifier () const
 
gr::io_signature::sptr input_signature () const
 
gr::io_signature::sptr output_signature () const
 
basic_block_sptr to_basic_block ()
 
bool alias_set () const
 
std::string alias () const
 
pmt::pmt_t alias_pmt () const
 
void set_block_alias (std::string name)
 
void message_port_register_in (pmt::pmt_t port_id)
 
void message_port_register_out (pmt::pmt_t port_id)
 
void message_port_pub (pmt::pmt_t port_id, pmt::pmt_t msg)
 
void message_port_sub (pmt::pmt_t port_id, pmt::pmt_t target)
 
void message_port_unsub (pmt::pmt_t port_id, pmt::pmt_t target)
 
virtual bool message_port_is_hier (pmt::pmt_t port_id)
 
virtual bool message_port_is_hier_in (pmt::pmt_t port_id)
 
virtual bool message_port_is_hier_out (pmt::pmt_t port_id)
 
pmt::pmt_t message_ports_in ()
 Get input message port names. More...
 
pmt::pmt_t message_ports_out ()
 Get output message port names. More...
 
void _post (pmt::pmt_t which_port, pmt::pmt_t msg)
 
bool empty_p (pmt::pmt_t which_port)
 is the queue empty? More...
 
bool empty_p ()
 
bool empty_handled_p (pmt::pmt_t which_port)
 are all msg ports with handlers empty? More...
 
bool empty_handled_p ()
 
size_t nmsgs (pmt::pmt_t which_port)
 How many messages in the queue? More...
 
void insert_tail (pmt::pmt_t which_port, pmt::pmt_t msg)
 
pmt::pmt_t delete_head_nowait (pmt::pmt_t which_port)
 
msg_queue_t::iterator get_iterator (pmt::pmt_t which_port)
 
void erase_msg (pmt::pmt_t which_port, msg_queue_t::iterator it)
 
virtual bool has_msg_port (pmt::pmt_t which_port)
 
const msg_queue_map_t & get_msg_map (void) const
 
virtual void setup_rpc ()
 Set up the RPC registered variables. More...
 
bool is_rpc_set ()
 Ask if this block has been registered to the RPC. More...
 
void rpc_set ()
 When the block is registered with the RPC, set this. More...
 
virtual bool check_topology (int ninputs, int noutputs)
 Confirm that ninputs and noutputs is an acceptable combination. More...
 
template<typename T >
void set_msg_handler (pmt::pmt_t which_port, T msg_handler)
 Set the callback that is fired when messages are available. More...
 
virtual void set_processor_affinity (const std::vector< int > &mask)=0
 
virtual void unset_processor_affinity ()=0
 
virtual std::vector< int > processor_affinity ()=0
 
virtual void set_log_level (const std::string &level)=0
 
virtual std::string log_level ()=0
 
- Public Member Functions inherited from gr::msg_accepter
 msg_accepter ()
 
 ~msg_accepter () override
 
void post (pmt::pmt_t which_port, pmt::pmt_t msg) override
 send msg to msg_accepter on port which_port More...
 
- Public Member Functions inherited from gr::messages::msg_accepter
 msg_accepter ()
 
virtual ~msg_accepter ()
 
virtual void post (pmt::pmt_t which_port, pmt::pmt_t msg)=0
 send msg to msg_accepter on port which_port More...
 

Static Public Member Functions

static sptr make (float omega, float gain_omega, float mu, float gain_mu, float omega_relative_limit)
 

Additional Inherited Members

- Protected Types inherited from gr::basic_block
enum  vcolor { WHITE , GREY , BLACK }
 
- Protected Member Functions inherited from gr::block
 block (void)
 
 block (const std::string &name, gr::io_signature::sptr input_signature, gr::io_signature::sptr output_signature)
 
void set_fixed_rate (bool fixed_rate)
 
void add_item_tag (unsigned int which_output, uint64_t abs_offset, const pmt::pmt_t &key, const pmt::pmt_t &value, const pmt::pmt_t &srcid=pmt::PMT_F)
 Adds a new tag onto the given output buffer. More...
 
void add_item_tag (unsigned int which_output, const tag_t &tag)
 Adds a new tag onto the given output buffer. More...
 
void remove_item_tag (unsigned int which_input, uint64_t abs_offset, const pmt::pmt_t &key, const pmt::pmt_t &value, const pmt::pmt_t &srcid=pmt::PMT_F)
 DEPRECATED. Will be removed in 3.8. More...
 
void remove_item_tag (unsigned int which_input, const tag_t &tag)
 DEPRECATED. Will be removed in 3.8. More...
 
void get_tags_in_range (std::vector< tag_t > &v, unsigned int which_input, uint64_t abs_start, uint64_t abs_end)
 Given a [start,end), returns a vector of all tags in the range. More...
 
void get_tags_in_range (std::vector< tag_t > &v, unsigned int which_input, uint64_t abs_start, uint64_t abs_end, const pmt::pmt_t &key)
 Given a [start,end), returns a vector of all tags in the range with a given key. More...
 
void get_tags_in_window (std::vector< tag_t > &v, unsigned int which_input, uint64_t rel_start, uint64_t rel_end)
 Gets all tags within the relative window of the current call to work. More...
 
void get_tags_in_window (std::vector< tag_t > &v, unsigned int which_input, uint64_t rel_start, uint64_t rel_end, const pmt::pmt_t &key)
 Operates like gr::block::get_tags_in_window with the ability to only return tags with the specified key. More...
 
void enable_update_rate (bool en)
 
buffer_sptr allocate_buffer (size_t port, int downstream_max_nitems, uint64_t downstream_lcm_nitems, uint32_t downstream_max_out_mult)
 Allocate a buffer for the given output port of this block. Note that the downstream max number of items must be passed in to this function for consideration. More...
 
- Protected Member Functions inherited from gr::basic_block
 basic_block (void)
 
 basic_block (const std::string &name, gr::io_signature::sptr input_signature, gr::io_signature::sptr output_signature)
 Protected constructor prevents instantiation by non-derived classes. More...
 
void set_input_signature (gr::io_signature::sptr iosig)
 may only be called during constructor More...
 
void set_output_signature (gr::io_signature::sptr iosig)
 may only be called during constructor More...
 
void set_color (vcolor color)
 Allow the flowgraph to set for sorting and partitioning. More...
 
vcolor color () const
 
virtual bool has_msg_handler (pmt::pmt_t which_port)
 Tests if there is a handler attached to port which_port. More...
 
virtual void dispatch_msg (pmt::pmt_t which_port, pmt::pmt_t msg)
 
template<typename Derived >
std::shared_ptr< Derived > shared_from_base ()
 This is meant to be called by derived classes (e.g. block) to get a shared pointer internally. This is needed because std::enable_shared_from_this doesn't seem to work with derived classes in an inheritance hierarchy. More...
 
- Protected Attributes inherited from gr::block
std::vector< long > d_max_output_buffer
 
std::vector< long > d_min_output_buffer
 
unsigned int d_blkd_input_timer_value = 250
 
gr::thread::mutex d_setlock
 
const pmt::pmt_t d_pmt_done
 
const pmt::pmt_t d_system_port
 
- Protected Attributes inherited from gr::basic_block
std::string d_name
 
gr::io_signature::sptr d_input_signature
 
gr::io_signature::sptr d_output_signature
 
long d_unique_id
 
long d_symbolic_id
 
std::string d_symbol_name
 
std::string d_symbol_alias
 
vcolor d_color
 
bool d_rpc_set
 
gr::logger_ptr d_logger
 
gr::logger_ptr d_debug_logger
 Default logger. More...
 
msg_queue_map_t msg_queue
 Verbose logger. More...
 
std::vector< rpcbasic_sptr > d_rpc_vars
 
pmt::pmt_t d_message_subscribers
 

Detailed Description

Mueller and Müller (M&M) based clock recovery block with complex input, complex output.

This implements the Mueller and Müller (M&M) discrete-time error-tracking synchronizer.

The peak to peak input signal amplitude must be symmetrical about zero, as the M&M timing error detector (TED) is a decision directed TED, and this block uses a symbol decision slicer referenced at zero.

The input signal peak amplitude should be controlled to a consistent level (e.g. +/- 1.0) before this block to achieve consistent results for given gain settings; as the TED's output error signal is directly affected by the input amplitude.

The input signal must have peaks in order for the TED to output a correct error signal. If the input signal pulses do not have peaks (e.g. rectangular pulses) the input signal should be conditioned with a matched pulse filter or other appropriate filter to peak the input pulses. For a rectangular base pulse that is N samples wide, the matched filter taps would be [1.0/float(N)]*N, or in other words a moving average over N samples.

This block will output samples at a rate of one sample per recovered symbol, and is thus not outputting at a constant rate.

Output symbols are not a subset of input, but may be interpolated.

The complex version here is based on: Modified Mueller and Muller clock recovery circuit:

G. R. Danesfahani, T.G. Jeans, "Optimisation of modified Mueller and Muller algorithm," Electronics Letters, Vol. 31, no. 13, 22 June 1995, pp. 1032 - 1033.

Member Typedef Documentation

◆ sptr

Member Function Documentation

◆ gain_mu()

virtual float gr::digital::clock_recovery_mm_cc::gain_mu ( ) const
pure virtual

◆ gain_omega()

virtual float gr::digital::clock_recovery_mm_cc::gain_omega ( ) const
pure virtual

◆ make()

static sptr gr::digital::clock_recovery_mm_cc::make ( float  omega,
float  gain_omega,
float  mu,
float  gain_mu,
float  omega_relative_limit 
)
static

Make a M&M clock recovery block.

Parameters
omegaInitial estimate of samples per symbol
gain_omegaGain setting for omega update loop
muInitial estimate of phase of sample
gain_muGain setting for mu update loop
omega_relative_limitlimit on omega

◆ mu()

virtual float gr::digital::clock_recovery_mm_cc::mu ( ) const
pure virtual

◆ omega()

virtual float gr::digital::clock_recovery_mm_cc::omega ( ) const
pure virtual

◆ set_gain_mu()

virtual void gr::digital::clock_recovery_mm_cc::set_gain_mu ( float  gain_mu)
pure virtual

◆ set_gain_omega()

virtual void gr::digital::clock_recovery_mm_cc::set_gain_omega ( float  gain_omega)
pure virtual

◆ set_mu()

virtual void gr::digital::clock_recovery_mm_cc::set_mu ( float  mu)
pure virtual

◆ set_omega()

virtual void gr::digital::clock_recovery_mm_cc::set_omega ( float  omega)
pure virtual

◆ set_verbose()

virtual void gr::digital::clock_recovery_mm_cc::set_verbose ( bool  verbose)
pure virtual

The documentation for this class was generated from the following file: