Antenna Connectors

LoRaWAN gateways and end devices use different types of connectors including U.FL, SMA, RP-SMA, Type-N, and Type-N PR for connecting antennas and interface cables.

U.FL #

U.FL (‘U’ stands for ultra-small and ‘FL’ is just a series name assigned by Hirose) connectors are commonly used in gateways and end devices where space is of critical concern (similar: I-PEX, IPX, etc).

There are two types:

U.FL Male - These connectors are surface-mounted and soldered directly to the printed circuit board.
U.FL Female - These connectors come as part of a pigtail, usually an ultra-fine coaxial (fluorinated resin insulated) cable.

U.FL Male and U.FL Female connectors provide a very tight snap-in connection. They are lightweight, require a small mounting area, and feature a very small mated height. When mating, the tactile click sensation confirms the complete electrical and mechanical connection.

U.FL Male (right) and U.FL Female (left). Image courtesy of SparkFun Electronics

The following table shows some of their applications:

Application	Description
	Interface Cable: SMA to U.FL. Image courtesy of SparkFun Electronics
	Interface Cable: RP-SMA to U.FL. Image courtesy of SparkFun Electronics
	A half-wave antenna with U.FL termination. Image courtesy of SparkFun Electronics
	U.FL Male connector is soldered onto a PCB
	Interface cable: I-PEX to N-Type cable. Image courtesy of RAKwireless Technology Limited
	I-PEX to N-Type Cables are used to provide an interface for connecting external antennas such as LoRa, WiFi, GPS, and LTE. Image courtesy of RAKwireless Technology Limited

SMA #

SMA connectors use a screw-type coupling mechanism to create strong mechanical connections.

There are two types:

SMA Male
SMA Female

SMA Male connectors have a center pin and inner threads whereas SMA Female connectors have a center sleeve and outer threads.

SMA Male (right) and SMA Female (left). Image courtesy of SparkFun Electronics

Variations: The Reverse Polarity (RP) SMA connectors use the same outer shell, but change the gender of the inner pin. However, the signal polarity is not reversed. These reverse polarity connectors do not mate with SMA connectors.

There are two types:

RP-SMA Male
RP-SMA Female

RP-SMA Male connectors have a center sleeve and inner threads whereas RP- SMA Female connectors have a center pin and outer threads.

RP-SMA Male (right) and RP-SMA Female (left). Image courtesy of SparkFun Electronics

The following table shows some of their applications.

Application	Description
	An SMA Female Edge-Mount connector is soldered onto a PCB. Image courtesy of Adafruit Industries
	Interface Cable: SMA to U.FL. Image courtesy of SparkFun Electronics
	Interface Cable: RP-SMA to U.FL. Image courtesy of SparkFun Electronics
	An omni-directional rubber ducky antenna with SMA connector.

N Type #

N Type connectors are threaded, waterproof, medium-size RF connectors that can be used to connect antennas (LoRa, LTE, GPS, WiFi, etc) directly or using cables.

There are two types:

N Type Male - these connectors have a center pin and inner threads. There is a ferrule between the center pin and the inner threads.

N Type Female - these connectors have a center sleeve and outer threads.

Variation: Like SMA connectors, N Type connectors have reverse polarity variations known as RP-N Type connectors.

There are two types:

RP-N Male - these connectors have a center sleeve and inner threads. There is a ferrule between the center pin and the inner threads.

RP-N Female - these connectors have a center pin and outer threads.

The following table shows some of their applications.

Application	Description
	An antenna feeder line which consists of N Type Male (right) and N Type Female (left) connectors. Image courtesy of RAKwireless Technology Limited
	RAK7249 WisGate Edge Max uses 4 N-Type connectors for connecting LoRa, LTE, GPS, and 2.4G WiFi antennas. Image courtesy of RAKwireless Technology Limited