Bluetooth Testing using LadyBug LB479A and LB480A Power Sensors

Bluetooth is a global wireless standard for simple, secure connectivity over limited distances. The standard lists several power level ranges that must be strictly adhered to. Bluetooth devices are divided into Power Classes. Power is specified as Peak Power and Average Power. All classes except BLE (Bluetooth Low Energy) specify a peak power of +23dBm (200mW), BLE specifies +13dBm (20mW). Class 1 is the highest power level Bluetooth Class and BLE is the lowest. Table 1, lists the general power specifications.

Bluetooth Testing LB480A

 

LADYBUG POWER SENSORS


BLE (Bluetooth Low Energy) is designed to transfer small bursts of data using appropriate modulation methods. BLE is not suitable for voice communication and is currently intended to send short pieces of data. Low power consumption is achieved largely by keeping its radio off most of the time. BLE scans only three advertising channels, and its radio is active only to send or receive short bursts of data. The packet size varies from 8 to 27 octets. BLE also sets up connections very quickly, which reduces the radio’s on-time further. BLE can transmit authenticated data in as little as 3ms, versus the 1000ms typical for Bluetooth. Time gated triggering measurements are helpful in measuring BLE signals.

Bluetooth Specifications

Sensor

Bluetooth Device  -Power Class

Max Peak
Power

Average
Power

BT Power
Control

Recommended
Sensor

Recommended
Attenuator

Class 1

+23 dBm

0 dBm to +20 dBm

Required

LB479A /LB480A

10 dB

Class 2

+23 dBm

-6 dBm to +4 dBm

Optional

LB479A /LB480A

6 dB

Class 3

+23 dBm

Less than 0 dBm

Optional

LB479A /LB480A

6 dB

BLE

+13 dBm

-20 dBm to +10dBm

Optional

LB479A /LB480A

Optional

Table 1 General Power Specifications

LadyBug LB479A and LB480A power Sensors are ideal for making accurate measurements on the Bluetooth signal. The sensors are first tier NIST traceable; this means the transfer calibration was done with a sensor calibrated directly by NIST, no better calibration is available. The sensors are ideal for Bluetooth development and manufacturing test systems. The LB479A can make statistical pulse measurements including peak and average power, plus crest factor on active signals. Internal and external triggering is standard on the LB480A, making flexible time gated measurements possible.

The LB479A and LB480A have very good sensitivity and speed when measuring average and pulse power. This makes them ideal for radiated measurements as well as for the direct measurement of BT devices. Statistical measurements down to -60dBm can be achieved with averaging.

Bluetooth Testing LB479AA

When connecting directly to the Bluetooth transmitter, an attenuator is recommended. Proper attenuator assures that the sensor will not be overloaded and that the signal will be in the ideal measurement range for the average and peak power levels. Refer to Table 1 for recommended attenuators.

LadyBug LB479A & LB480A Sensor Features & Primary Specifications

Property / Sensor

LB479A

LB480A

Competitive Sensors7

Frequency Range

10 MHz to 8 GHz

50 MHz to 8 GHz

Less

Bandwidth

10 MHz

10 MHz

5 MHz Typical8

Dynamic Range

80 dB

80 dB

Typically 50 dB

Triggering Capability

Optional

Internal/Ext In & Out

Not available

Thermally stable6

Yes

Yes

No

Requires Zero before use

No

No

Yes1

Interrupts to zero

No

No

Yes2

Settled Meas. Rate

2000/sec

2000/sec

33+/sec  Varies5

First Tier Calibration3

Yes

Yes

No

Connector Options

Yes

Yes

No

Warranty4

3 years

3 Years

1 Year

1-No Zero before use: Stated for low power high accuracy measurements, competitive sensors may not recommend (or support) zeroing depending upon quality. 2-Quality competitive sensors will stop measuring to zero, this interrupts automated measurements; LadyBug Sensors dynamically adjust and do not pause or stop to zero, however they do maintain full accuracy. 3-Transfer Calibration directly from a National Primary Standard’s lab such as NIST, NPL, PTB, ETC. 4-Anritsu & Minicircuits 1yr; Keysight & RS 3yrs; 5-Unbefferred reading & settled measurement speed-competitively priced sensors. 6-LadyBug Sensors employ patented active thermal management. 7-Sensors in the similar price range. 8-Varies. For similarly priced competitive sensors.

Data Sheets & Order Guides