Abstract: This standard specifies the architecture, abstraction layers, interfaces and metadata requirements for Spectrum Characterization and Occupancy Sensing (SCOS) system, and defines performance parameters, units and measures. This SCOS system comprises one or more Spectrum Sensing Devices which scan electromagnetic spectrum, digitize it and perform processing, transmitting the resultant data with appropriate metadata to a central storage and processing system, according to rules, policies or instructions imposed on the Spectrum Sensing Devices by a management system. Keywords: radio spectrum sensing, spectrum monitoring, signal characterization, cognitive radio, IEEE 802.22.3, WRAN standards
NAME: SDID DATA TYPE: string Required The unique ID assigned to the sensing device. The maximum length is 64 octets. NAME: calibrateStatus DATA TYPE: Integer Conditional The status code for the scheduled calibration. NAME: envInfo DATA TYPE: envMetadata Required The type of DCli. The maximum length is 64 octets. NAME: healthInfo DATA TYPE: healthMetadata Required The SD health metadata as described in B.3.8. Table 23describes the healthMetadata JSON object sent by the SD to TM. Table 23 SD Health Meatadata Object Definition Parameter R/O/C Description NAME: batteryLevel DATA TYPE: Integer Required The battery level in percentage rounded to closest integer. SD-TM Disassociation Message Exchange Table 24describes the sdDisassociateRequest JSON object from SD to TM. Table 24 SD Disassociate Request Object Parameter R/O/C Description NAME: SDID DATA TYPE: string Required The ID assigned to SD by the SCOS operator. The maximum length is 64 octets. NAME: SDName DATA TYPE: string Required The name of the sensing device registered with SCOS operator. The maximum length is 64 octets. NAME: SCOSOperator DATA TYPE: string Required The name of the SCOS operator. The maximum length is 64 octets. Table 25 describes the sdDisassociateResponse JSON object from TM to SD. Table 25 SD Disassociate Response Object Parameter R/O/C Description NAME: SDName DATA TYPE: string Required The name of the SD registered with SCOS operator. The maximum length is 64 octets. NAME: SCOSOperator DATA TYPE: string Required The name of the SCOS operator. The maximum length is 64 octets. NAME: status DATA TYPE: string Required The response code for dissociation request. NAME: oldSDID DATA TYPE: string Required The SD ID that has been dissociated The maximum length is 64 octets. DCli<>TM Messages Following table describes the SCOS Data Request API methods
SD<>DM Messages Table 40 denotes the messages exchanged between SD and DM. Table 40 Messages Exchanged Between SD and DM scos_method_name JSON Array Name of Request Message JSON Array Name of Response Message “sd_dm_associate” sdAssociateRequest sdAssociateResponse “sd_dm_publish” sdPublishRequest sdPublishResponse “sd_dm_heartbeat” sdHeartbeatRequest sdHeartbeatResponse “sd_dm_disassociate” sdDisassociateRequest sdDisassociateResponse SD-DM Association Message Exchange Table 41 describes the sdAssociateRequest JSON object from SD to DM. Table 41 SD Associate Request Message Parameter R/O/C Description NAME: SDName DATA TYPE: string Required The name of the sensing device registered with SCOS operator. The maximum length is 64 octets. NAME: response DATA TYPE: string Required The response code for association. NAME: SDID DATA TYPE: string Required The unique ID assigned to the sensing device. The maximum length is 64 octets. NAME: heartbeatInterval DATA TYPE: Integer Required Heartbeat interval in seconds. SD-DM Publish Message Table 42 describes the sdPublishRequest JSON object from SD to DM. Table 42 SD Publish Sensing Data Message Parameter R/O/C Description NAME: SDID DATA TYPE: string Required The unique ID assigned to the sensing device. The maximum length is 64 octets. NAME: TaskID DATA TYPE: String Required Unique ID for the Spectrum Scan. The maximum length of the ID string is 64 octets.
SD-DM Heartbeat Message Table 45Table 45 describes the heartbeat message exchanged between SD and DM Table 45 SD Heartbeat Request Message With DM Parameter R/O/C Description NAME: SDID DATA TYPE: string Required The unique ID assigned to the sensing device. The maximum length is 64 octets. NAME: Cmd DATA TYPE: Time Optional If nonzero, SD is given a command. Currently, two command codes are defined. If cmd is 1, DM is asking SD to list all topics for which the SD is publishing. If cmd is 2, DM is asking to stop publishing for a topic or all topics as suggested by next object in the message. NAME: topic DATA TYPE: string Conditional If cmd is 2, this field denotes the topic for which DM is asking SD to stop publishing. If no topic is specified, DM is asking to stop publishing for all the topics. Table 46 denotes the topic details exchanged in the heartbeat response message from SD and DM. Table 46 Topic Details Exchange in Heartbeat Message Parameter R/O/C Description NAME: SDID DATA TYPE: string Required The unique ID assigned to the sensing device. The maximum length is 64 octets. NAME: activeTopics DATA TYPE: Array of string Required Each entry in the list describes an active topic. The maximum length is 64 octets. SD-DM Dissociation Message Exchange Table 48 describes the sdDissociateRequest JSON object from SD to DM. Table 47 SD Dissociate Request Message Parameter R/O/C Description NAME: SDID DATA TYPE: string Required The ID assigned to SD by the SCOS operator. The maximum length is 64 octets. NAME: SDName DATA TYPE: string Required The name of the sensing device registered with SCOS operator. The maximum length is 64 octets. NAME: SCOSOperator DATA TYPE: string Required The name of the SCOS operator. The maximum length is 64 octets. Table 48 describes the sdDisassociateResponse JSON object from DM to SD.
NAME: timestamp DATA TYPE: Time Required Timestamp with the associated scanning output. NAME: scanData DATA TYPE: Array of scanData objects Required Array of scanData objects. Each object represents SD measurements for the freqInterval. The scanData is defined in B.3.27.2 NAME: envInfo DATA TYPE: environMetadata Required The environmental data including , temperature, and humidity as described in B.3.8 Table 55 describes the scanData JSON object from DM to DCon. Table 55 DM Published Data Object Definition Parameter R/O/C Description NAME: dataFormat DATA TYPE: Integer Required The format of the output data as specified in B.3.27.2. NAME: sizeData DATA TYPE: Integer Required The number of measurements. NAME: measData DATA TYPE: Array of Complex Required The complex measurement values. The size of the array is defined by sizeData. Table 56 describes the dcTopicDataResponse JSON object from DCon to DM. Table 56 Topic Data Acknowledgement Message from DCon Parameter R/O/C Description NAME: DCID DATA TYPE: string Required The unique ID assigned to the Data Consumer. The maximum length is 64 octets. NAME: TopicID DATA TYPE: String Required Unique ID for the Topic. The maximum length of the ID string is 128 octets. NAME: status DATA TYPE: Array of Integer Required Each entry shows status for the TopicData request of the scanning data for each of the freqIntervals. NAME: timestamp DATA TYPE: Time Required Timestamp for the associated scanning data that DC is acknowledging. DC-DM Unsubscribe Message Exchange Table 57 describes the dcUnSubscribeRequest JSON object from DC to DM.
Range (min/resolution/max) 1° Current Elevation Beam Direction Current elevation Beam Direction indicates the current direction of the antenna main beam in elevation plane. It is expressed in degrees from horizontal plane and it is included in a range that has Antenna.Min.Elev.Beam.Dir. as lower boundary and Antenna.Max.Elev.Beam.Dir. as upper boundary. Metadata name: Curr.Azi.Beam.Dir Meas. Unit: ° (degree) Data type: Fixed-point ID: 003 Size: 1 Desc.: It indicates the current direction of the antenna main beam in elevation plane. Range (min/resolution/max) 1° RF Front-End Metadata The RF Front-End metadata indicates specifications of the RF front-end as given by the manufacturer. The definition of each parameters and the related unit of measurements are reported in table A4. Metadata name: Front-End Meas. Unit: -------- Data type: Cluster ID: 004 Size: Variable Desc.: List of the RF Front-End specifications according to manufacturer specifications. .0 Front-End.Low.Freq.Passband Data type: Unsigned fixed-point .1 Front-End.High.Freq.Passband Data type: Unsigned fixed-point .2 Front-End.Low.Freq.Stopband Data type: Unsigned fixed-point .3 Front-End.High.Freq.Stopband Data type: Unsigned fixed-point .4 Front-End.LNA-Gain Data type: Float .5 Front-End.LNA-NF Data type: Float .6 Reserved (for future use) Table : Front-End metadata parameters description Name Content Meas. Unit: Front-End.Low.Freq.Passband Low passband frequency evaluated at -1 dB Hz Front-End.High.Freq.Passband High passband frequency evaluated at -1 dB Hz Front-End.Low.Freq.Stopband Low stopband frequency evaluated at -60 dB Hz Front-End.High.Freq.Stopband High stopband frequency evaluated at -60 dB Hz Front-End.LNA-Gain Low Noise Amplifier Gain dB Front-End.LNA-NF Noise Figure of Low Noise Amplifier dB
Normative Functional Requirements Data Quality and Definition Data acquired must be accompanied by adequate metadata information to allow for duplication of the measurement or assessment of data quality by a subject matter expert. Hardware specification and measurement parameters are to be included in the messaging metadata requirements. Information less amenable to metadata capture should be made available via appropriate and accessible documentation, e.g., algorithm described via written article with source code in Github repository. Regulatory requirements This standard should provide mechanisms to meet the regulatory requirements of national operators that have defined parameters or requirements for spectrum sensing in various applications. These regulatory requirements would take two forms: the first is technical requirements for sensitivity, resolution, etc. The second is limitations on how and where sensing might be done where there are sensitivities around privacy, military use and other national policies and regulations. Policy Management and Enforcement Requirements To allow for granularity in what the SCOS systems can do, but also ensure spectrum occupancy or utilization data is not exposed in contravention of national policy or regulation, it is proposed that the TM would be able to apply policies to allow or disallow certain functionality in the SDs, or disallow transmission of the data to third party systems. These policies would be determined by the TM operator in accordance with their requirements and that of local authorities (e.g. a national regulator or network operator), and cascaded down to any connected SDs. These policies would allow sensing only according to allowed metrics (e.g. no hi-resolution raw scans in military radar bands), and limit sensing data transmission to certain classes of third party systems.
Informative: Regulatory Technical requirements Various countries will have differing requirements here, but a few countries already have definitions in place that should be observed. For example, in the FCC rules for the VHF/UHF TV bands, the FCC requires a spectrum sensing detection accuracy as specified by the Table 1: FCC Sensing sensitivity requirements. Table 1: FCC Sensing sensitivity requirements Regulatory domain Type of signal Sensing detection threshold (in dBm) Data fusion rule for distributed sensinga Monitoring requirements USA ATSC –114 (averaged over 6 MHz) “OR” rule Detection threshold referenced to an omni-directional receive antenna with a gain of 0 dBi USA NTSC –114 (averaged over 100 kHz) “OR” rule Detection threshold referenced to an omni-directional receive antenna with a gain of 0 dBi USA Wireless microphone –107 (averaged over 200 kHz) “OR” rule Detection threshold referenced to an omni-directional receive antenna with a gain of 0 dBi aThe value “1” indicates detection. Other requirements for the 2.7 GHz to 3.7 GHz band shall be defined based on the evolving regulations. For example, the spectrum sensing devices in the 2.7 GHz to 3.7 GHz can sense for Radar Signals and provide that information to the Spectrum Access System (SAS) that is being defined in these bands.